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He really didn’t mean to fall in love with her in the exact way he had. Sure, he had fallen in love with her kindness, her generosity, and all the ways she made him smile. To be so deeply entrenched in the throes of love by her very presence and being, however, was not something he anticipated. Sans knew that (Y/n) was a gentle soul, capable of caring and loving everyone she met without a second glance. He had experienced it firsthand when the monsters emerged from the Underground, as she was among the first people to help monsterkind to get food and supplies. Her soul was practically screaming kindness at him, and it wasn’t long before she proved it to all the monsters she interacted with. The way she was able to give all of the monsters care and attention while still handling her normal duties was fascinating to him. Sans knew in his soul that she would be great friends with him and Papyrus, and perhaps even his brother’s datemate! As she made her rounds back to the skeletons, Sans himself had insisted on the two getting together to see each other again. From there, friendship sprouted between the three of them, though Sans discovered quickly that Papyrus wasn’t interested in romance at the moment. The shorter of the two skeletons was initially disappointed by this factor, but (Y/n) was still their friend, no matter what. As their time on the surface grew from days to months, to eventually years, Sans found himself inexplicably drawn to (Y/n)’s soul. Her kindness would often get her in trouble, as too many people were willing to exploit her for all they could, so he designated himself as her personal guard. There was hardly a place that he would go without her, though she didn’t seem to mind too much. He didn’t know he had fallen in love until he was talking to her about her day, three years after they had met. She was babbling on about how she disliked one of her co-worker’s attitude about monsters, and how she tried to handle it. Sans found himself utterly enraptured by her, staring openly at her beauty and the way her expression would change rapidly. Everything about her was so beautiful, and it was then that he was struck with the realization that he never wanted this to stop. Sans didn’t want her to ever stop talking to him about her day, to come to him when she was upset. He was determined that she should be able to keep him at all times, and he wanted to keep her safe. His soul ached at the mere thought that she might ever get hurt, and he knew that she was the one he wanted to spend all of his time with and share his soul with. This made for some awkward interactions with her later, as he wasn’t sure how she felt, but Sans did his best to cover it up. One particular evening, (Y/n) had taken him into her home, something that was frequent now with him following her for safety, for a cup of tea. Sans had heartily accepted, and sat himself down on her couch, humming a soft tune to himself while he waited. Not two minutes had passed before he heard the sound of glass shattering and he leapt up, dashing into the kitchen as quickly as he could. “(Y/n)!!” he called out as he ran. “Are you alright?? What happened, I heard something breaking!” Upon entering the kitchen, he found shards of a mug on the ground and (Y/n) holding her foot with one hand, the other against the counter. Blood was dripping through her fingers, and she looked up at him, eyes wide. “I’ll be okay, Sans,” she said, trying to send him a disarming smile that ended up more like a grimace. “I just dropped one of the mugs I was trying to get and I think I may have stepped on a piece, but it’s fine! I can just-” “NO!” Sans cried before he could stop himself, hurrying over to her and quickly clearing the broken pottery with his magic. “You’re hurt and bleeding and need proper care at once! Not to worry, the Magnificent Sans shall take care of you!” He quickly scooped her up off the floor and set her down on the counter, surprising (Y/n) based off the squeak she made in protest. Sans knew that even though he was just barely taller than her, he was much stronger than he let on, and could easily do tasks like this. Immediately after he set her down, he knelt by her foot to work on pulling out any pieces lodged there. The kitchen grew quiet for a moment as he began to work healing magic into (Y/n)’s foot. “My knight in shining armor,” (Y/n) said after a few moments, an amused tone to her voice. “You always do so much for me, keep me safe, and you never once ask for anything in return. Why?” Sans looked up in surprise, certain that his eye lights were shifting into stars at the question. “I… I don’t know what you mean,” he said, turning his attention back to her foot in an effort to try and hide the glowing blue blush that now was coating his cheekbones. (Y/n) let out a laugh above him, the kind that made his soul soar with joy in his ribcage. “Sans, you’re a terrible liar,” she mused, rapping on the back of his skull gently with her knuckles to get his attention. “You have done so much to take care of me and make sure that I have the best of everything that I could ever want. You even tried to set me up with your brother, which is really weird, but there’s something driving you to do all of this for me, isn’t there? Why would you-” (Y/n) never got to finish her question because Sans abruptly stood up and kissed her, his hands coming to rest on her shoulders. For a moment, he almost panicked because she sat completely still and made no motions to kiss back. Then, as quickly as his soul-wrenching worry started to bloom, it withered when (Y/n) snaked her arms around his neck and began to kiss back. For several minutes, neither of them said anything, simply kissing as (Y/n) sat on the kitchen counter. Gradually, Sans allowed his hands to slide off her shoulders to wrap around her waist, tugging her closer to him. When they finally broke away from each other, Sans could see the reflection of his blush in her eyes. Her face was also flushed with pink, and a smile was on her lips, which he could feel himself mirroring. “I’ve wanted to do that for some time now,” she admitted with a soft laugh. “Always wondered what it would be like to kiss my very favorite skeleton.” Sans could feel his blush beginning to intensify on his cheekbones, but he maintained what little composure he had left from his bold actions. “Well, I… I wanted to know what it was like to kiss my very favorite human for a really long time too,” he said, trying to use her words against her as well. “The reason I keep doing things for you is because I love you, (Y/n). I… I ache in my soul whenever I’m not around you, I can’t stop thinking about you and… And I want to share my soul with you.” (Y/n)’s eyes widened at that sentence, having already heard from other monsters that this was the most vulnerable and personal thing a monster could do. Sans put a finger on her lips before she could respond to his statement. “I understand if you need some time to think about it, and I’m not asking you to make a decision now!” he said hastily, nervousness starting to grow. “If you want to, I would be more than happy to simply start as datemates, and I can wait. I’ll wait for as long as you need to, so don’t worry about trying to decide right away about the soul sharing.” Sans was a little proud that he was able to pull the entirety of that sentence off without stuttering, despite the tension he was feeling. “I… Stars, what do I even say to that?” (Y/n) breathed, leaning away a little to run her fingers through her hair. “You’re just so sweet and, and kind, and I’m just… I… I need some time before I can say that I’ll share my soul with you, but I would love to start as datemates, Sans. I can be your girlfriend, that much I can say.” Sans’ soul soared with joy again and he kissed her on the cheek gently, feeling his energy begin to vibrate. (Y/n) laughed and caught him in another kiss on the teeth, humming softly into the gesture while he pulled her in closer. That was the beginning of their relationship, and very quickly Sans grew to be even more protective of her. He made sure to shower her with affection and love, and she was more than happy to reciprocate it. A year after they had begun dating, (Y/n) told him she was ready to share her soul with him, which nearly sent him over the moon. Once the two had bonded, Sans found out very quickly that he liked more than anything else that (Y/n) was willing to play the part of his dutiful mate. Certainly he didn’t just leave her to her own devices and huge messes for her to clean up, but she took some of the stress away. Sans loved nothing more than returning home to find something done for him, then to give her a reward afterwards. About six months after the pair had been living together, Sans found himself starting to get more and more possessive of (Y/n). She wasn’t allowed to leave his sight, and he was keeping a very close eye socket on her at all times. Papyrus wasn’t even allowed near her, something that startled both his brother and (Y/n) when it occurred. “Why can’t I give Papyrus a hug, Sans?” (Y/n) asked, looking a little hurt that her mate was refusing such a simple gesture. “We haven’t seen him in ages and I’ve missed my punny friend!” “You just can’t!” Sans said, balling up his fists and glaring his older brother down with vehemence. Instead of trying to further explain himself, he wrapped his arms around her midsection protectively, actually growling at Papyrus a little bit. Fortunately, the elder skeleton seemed to understand what was happening and started to chuckle, his hands shoved into his hoodie pocket. “I get it, Sans,” he drawled with an amused smirk. “I shouldn’t be gettin’ too close to your baby, now should I?” (Y/n) froze at the statement, turning her head to look at Sans with wide eyes. He was holding firm, but didn’t seem too shocked at the choice of words Papyrus had spoken. She knew for a fact though that he never called her “baby” as a pet name or anything similar, so that could only mean…. “Yes, my sweet (Y/n),” Sans said, almost sighing as though it should have been obvious. “You’re pregnant, and he is not allowed to touch you while you are so delicate! I have to make sure that you and the baby are protected at all times, no matter what now, and even though he is my brother, I cannot take any risks!” “I- oh stars, Sans, we’re having a baby??” (Y/n) cried, flinging his arms off her body so she could turn to face him. “Why didn’t you say something sooner if you knew already? This is, this is incredible! You’re going to be a dad, I’m going to be a mom, Paps is going to be an uncle, oh stars !!” Sans’ face broke into one of his classic smiles, and soon he was beaming back at her with joy and pride. “I was waiting to try and tell you when I could surprise you!” he said, planting a kiss on her cheek. “Although it seems that you were surprised already by the fact that you are pregnant, so I win anyways, regardless of if I had to plan it or not! No thanks to Papyrus for ruining it, I had a lovely dinner planned in a few days where I would make the most magnificent meal for us, so I could tell you.” He shot a pointed glare at his brother, who merely shrugged, smiling quite contentedly. “Sorry, bro,” he said, pulling out a lollipop to chew on in place of a cigarette. “I just couldn’t help but to tell the entire womb ‘bout this.” Sans started to tear into him about the pun, but (Y/n) stopped him with a kiss, too excited about the baby to care about anything else. The younger skeleton was more than happy to return the sentiment, and also eager to continue to make sure everyone knew who held (Y/n)’s soul. Sans was on hyper alert after that day, unabashedly taking care of (Y/n)’s wellbeing at all times without hesitation. He was quick to give her magic whenever she requested it, and even when he thought it necessary. He had known she was pregnant from almost the first week she had been pregnant, based on the soul she now carried in her womb. Pregnancy symptoms started to kick in around the sixth week, and Sans wished that magic would take care of all her problems. As of now, at two and a half months pregnant, (Y/n) was vomiting up last night’s dinner, at one in the morning. Sans had her hair pulled away from her face, concern etched into his features as she emptied the contents of her stomach. This was the fifth time in three days that (Y/n) had been unable to keep anything down, and Sans was worrying that she wasn’t getting enough nutrients. If nothing stayed in her stomach, she couldn’t properly feed the baby and herself. Worse yet, if this continued to be a problem, he would have to go to an outside source for help, which he absolutely didn’t want to do. He had very few things he could claim for himself in this world, but (Y/n) was a definitive one that he knew he had. Not that she was a mere possession, but a part of his soul was with her at all times, and vice versa. Sans rubbed her back soothingly as the poor woman groaned and retched into the toilet, trying to relieve what little tension he could. (Y/n) finally stopped once her stomach was just dry heaving, and sat back to flush the toilet and rinse her mouth. He handed her a cup of water and she took it gratefully. “This is getting to be a bit ridiculous,” she grumbled softly, her throat raw and aching from the acids she had just gotten rid of. “I haven’t been able to enjoy a good meal for the past five days, and I keep worrying that I’ll just start throwing up everywhere. I wish that I could skip this part and make it easier for the baby to get here.” Sans wrapped his arms around her waist gently, allowing some magic to seep into the skin of her stomach soothingly. “So do I, my sweet (Y/n),” he hummed, keeping his voice low in the quiet of the early hours. “But it is something we must endure so that our baby can be safe in this world, and I will do everything I can to make sure that you both are safe.” (Y/n) hummed in appreciation, leaning into his embrace tiredly. Sans carefully picked her up and carried her back to bed, hoping that his magic would be able to ease the aches she was feeling. Thankfully, as more time passed, (Y/n)’s morning sickness became a distant memory, though there were a few rare flare ups. As her stomach began to swell into a small bump, around month four, Sans found oddly enough that he liked seeing (Y/n) like this. She was so much softer now than she had been before, and there was a glow about her that wasn’t just because of his magic. When her stomach started to really grow, Sans couldn’t help but feel a sense of extreme pride when he watched her. Her womb had his child in it, and for whatever reason, that was the sexiest thing on the planet to him. Just to see her waddling around on a cool September day, her extended belly getting in the way of her normal activities was way sexier than it should have been to him, though he only admitted it to her when she wasn’t really paying attention. As a result of his newfound adoration, Sans thought often about how their family would end up in the future. Sure, they already had one baby on the way now, but when they were born, would (Y/n) want more? He certainly could get used to the idea of her looking like this more often, but if she didn’t feel the same way… Sans could cross that bridge when he got there. (Y/n)’s stomach only continued to fascinate him as her waistline disappeared into a large bump, and Sans found that he was spending every waking moment attached to her. He spoke to the baby near constantly, and she had told him more than once that his eye lights turned into hearts as he did so. It wasn’t any surprise then that he would cuddle up to her belly, giving the baby as much magic as they would take in a day. Unfortunately, someone in the media got a hold of how there was now a hybrid baby getting ready to enter the world, and the resulting emotions were… mixed. Some people were ecstatic that there would be a new sort of union between monsters and humans, but there were others who were less than thrilled. (Y/n) and Sans now received a constant stream of people blasting hatred at them through letters, social media, and even in public. Sans’ urge to protect (Y/n) grew all the more with this turning, and much as she tried to stop him, there were days when he came close to lashing out. The further into the pregnancy (Y/n) got, the worse the insults became. People were calling her a traitor, a monster sympathizer, and worse. The stress was getting to be too much for her, and Sans had to calm her down several times from panic attacks to help her and the baby. Then, when (Y/n) was two days past when she should be due, the worst thing that could have happened came to life. Sans was just returning from his shift as a security guard for a local, yet lucrative, mall center. The day was tiring, and he wanted nothing more than to simply curl up with (Y/n) and discuss baby names some more while eating whatever would satisfy her latest craving. The baby had been getting restless as of late, and Sans also wanted to make sure they had sufficient magic for the day, despite the fact that he gave them magic every day. Upon returning home, however, he noticed two very, very wrong things about his home. The first of which was that the front door was wide open, which Sans knew was something neither he or (Y/n) ever did. When he took a closer look at it, the door appeared to have been kicked open, and Sans’ soul plummeted in his ribcage. The second thing that was wrong was that (Y/n) was notably missing from the house, the presence of her soul gone. There were signs of a struggle inside, where furniture had been kicked over and a few pictures and glassware smashed. It seemed as though (Y/n) had tried to fight off whoever it was even though she was in no condition to do so. A tiny part of Sans was proud of that, but his soul was screaming to find her, overriding the pride. Just as he was about to call Alphys and Papyrus for help, his phone started to ring from an unknown number. Sans answered it immediately, not wanting to keep whatever psychopath had kidnapped (Y/n) from waiting too long. “Hello, Mr. Gaster,” the voice said coolly, and from what he guessed, it sounded like a man’s voice. “I’m sure you’ve already guessed that we have your wife with us.” “Where is (Y/n),” Sans spat out, gritting his teeth together. The man on the other end chuckled at this, only adding fuel to Sans’ rage. He could feel her soul panicking with the small piece he had, and she wasn’t calm enough to allow him to find her location yet. He just needed a few minutes on the phone, and he could get to her. “My my, eager to hear about the details already?” the man responded. “Here, I’ll put you on speaker so you can hear her for just a few moments. Go on, dolly, tell your husband how much you miss him.” There was a soft click, indicating that the man had indeed put him on speaker, and Sans’ soul twisted in fear. “(Y/n)??” he said, hoping to hear her voice. She responded with his name, and for a moment the tightness in his soul was eased, if only for a moment. “Sans, whatever they want, don’t do it!” she cried out, and Sans could almost feel the pain she was in. “I’ll be fine, you can get us out of this, just don’t-!! Oh stars....” His soul leapt in fear at the sound of her quiet groan and the man snapped at her, demanding that she tell him what happened. “(Y/n), what happened?” Sans asked, and upon receiving no immediate response, he began to panic. “(Y/n)??” “Sans, call Papyrus and get help,” she said, her voice trembling slightly. “My water just broke and-” The call was abruptly taken off of speaker and the man’s voice replaced (Y/n)’s, his tone now harsh and cruel. “You have three hours to get the monsters to agree to go back Underground or your wife and child will pay the price with their lives,” the man growled, and the call cut off. Sans stood there, shaking for a moment, before he bolted back out of his house to run to Papyrus’. He called his brother on the way and explained the situation, knowing that (Y/n) needed more than just her knight in shining armor. Not twenty minutes later, Asgore, Toriel, Papyrus, Alphys, and Undyne had all been gathered around Papyrus’ dining room table. Sans was pacing nervously, still trying to get a read on where (Y/n)’s soul was located while the others discussed the man’s terms. “We can’t just let him walk all over us and force us to go back Underground!” Alphys shouted, pounding a fist down on the wooden surface. “We fought hard to get our freedom, so why should we just lie down and give it up now?” “Keep in mind, Alphys,” Papyrus said coolly, shooting the woman a steely glare, “that my niece or nephew’s life is also on the line in this. I don’t wanna lie down and take it either, but we gotta look at the facts that two lives are in the mix here.” “So all of the Underground is worth two lives??” she cried out, flinging her hands up in the air. A blue bone suddenly shot up in front of her at the table, almost knocking the lizard woman in the chin, and Alphys immediately stopped to turn and look at Sans. His eye sockets were dark with rage, something she had never seen happen before, and his usual smile looked almost maniacal. “D O N T Y O U D A R E T A L K A B O U T M Y M A T E L I K E T H A T,” he seethed, voice matching the dark expression that he wore. Alphys gulped and sat back down in her seat, and in return, Sans dissipated the bone from in front of her. Toriel sighed and folded her arms in front of her. “We cannot agree to the terms he has laid out in front of us, but neither can we risk the lives of two innocents,” she said, quietly musing to herself. “Quite a dilemma, and now that (Y/n) has gone into labor, it will only be easier for them to hold that above our heads.” “Perhaps we can reason with them,” Asgore supplied, looking around the table. “If there is a way that they will change the terms and spare both (Y/n) and the child-” “W-we know they won’t do that, y-your majesty,” Undyne said, fiddling with the webbing between her fingers. “If we d-don’t comply with their demands the way they want, sh-she will die for certain.” “Sans, have you been able to find where (Y/n)’s soul is yet?” Papyrus asked, turning to look at his brother worriedly. The younger skeleton was close to it, but he hadn’t so he shook his head morosely, still pacing back and forth. His soul was screaming at him now, and he could feel (Y/n)’s pain from wherever she was being held. As the arguing continued, Sans reached out with his soul to (Y/n), hoping that she would be able to sense his presence. For a moment, he felt her calling back out to his, and he was able to see what she was seeing. It appeared to be an office building of some sort, and he noticed that she could see the town hall from the window. That was all he needed, and Sans sent a wave of reassurance her way to let (Y/n) know that help was on the way. “I’ve got where she’s at,” Sans said, and instantly everyone was paying attention to what he was saying. He quickly relayed where they were keeping (Y/n) and the group quickly came up with a rescue plan to get her back. All the monsters headed out, Sans and Papyrus teleporting quickly to the building’s location to act as decoys while the others made their way there. Sans was about to rush in when Papyrus caught him by the back of his scarf, to which the younger skeleton protested greatly. “Papyrus, I have to go in there!” he cried out, his soul shrieking the same sentiment to him. “(Y/n)’s in pain and our baby is on its way into the world! I have to be there to help her!” “But we gotta stick to the plan, Sans,” Papyrus said calmly. “If you go charging in there, there’s a chance that they could just kill her anyway. (Y/n) can last another few minutes while we get everyone into the appropriate places to get her out of there. But it’ll only work if you stick with the plan that you helped make , got it?” Much as Sans wanted to argue, Papyrus was right, and he reluctantly went in with his brother to the building. He called the number on the phone again and told the man all the right things, to which the man gave them the address to meet him at. Sans was itching to get up there, to sweep (Y/n) into his arms and take her back to a hospital or something so she could give birth appropriately. Soon, Papyrus got the signal from everyone else that the plan was set to go, the police set up outside to get the kidnappers while Sans went in to get (Y/n). Papyrus had to stay outside, but Sans barely noticed his absence in the wake of the fury rising in his soul. He managed to stay calm long enough to make his way into the room, only to see (Y/n) was no longer there. “Oh, so you came in just like that,” the man said, his face obscured by a mask he was wearing. “I almost worried that you weren’t coming, based on the time it took from our little chat over the phone.” “Where is (Y/n),” Sans said, not posing it as a question but as a demand. “I held up my end of the deal, now where is she?” The man waved a hand to another person in the room, also wearing a mask, and he went out, dragging (Y/n) in behind him by the back of her shirt. Sans’ soul cried out in relief as she appeared relatively unharmed, and he rushed to her side. It had only been about an hour or so since he had received the first call from these people, but she was panting and whining already. The man began to speak again, but before he got to speak, the police came rushing in to arrest the people responsible parties. There were apparently several other people that were involved in that operation that were elsewhere in the building. The police came and pulled all the kidnappers outside, who were a part of a large monster protesting group. When the people right around Sans and (Y/n) had been taken care of, Sans started to get ready for her to move out. As soon as he started to pick her up, however, she let out a cry of pain, and he was quick to set her back down. “What’s wrong, my sweet (Y/n)??” he asked, urgency filling his voice. “We have to go now and get you to the hospital, are you hurt somewhere??” (Y/n) gripped his shirt sleeve tightly, and shook her head. “Sans, the baby is coming,” she wheezed out, and let out a whine at his confused look. He looked at her and almost started laughing, knowing that she was already in labor. He planted a gentle kiss to her cheek and started to try again, though she pushed him off. “I know the baby’s coming, that is why we have to-” “No, Sans, they are coming right now ,” (Y/n) said, her body tensing up with a contraction, and Sans froze. “We don’t- ngh!! We don’t have time to get to the hospital, the baby is coming now!! ” (Y/n) seized his hand and began to push, even though she was still wearing her pants from earlier. Sans quickly pulled out his phone and texted Papyrus, then got to work on wiggling (Y/n) out of her clothing, as she instructed him to. He knelt carefully between her knees, doing his best to keep her from panicking while his excitement at being a father came rushing back to him. This was happening, and it was happening so quickly that he wasn’t sure of what exactly to do with himself. Thankfully, (Y/n) seemed to have a great grip on the situation, taking care of her breathing and pushing fairly well. Sans gave her plenty of encouragement, holding her hands and kissing her forehead soothingly. Before even five minutes had passed, based on the clock on the wall, Sans could see the baby’s head appear and he gasped reflexively. “They’re almost here!!” he squealed, certain that his eye lights were either stars or hearts by now. “Our baby is almost here, (Y/n), you can do it, I believe in you!!” His words of encouragement boosted her confidence, and a minute later, Sans was able to catch the baby in his arms. They were a skeleton, through and through, no doubt because of his regimented magic sharing with them. He could also tell that it was a little girl he was holding, and while her magic and soul were very strong, they also seemed to waver faintly. For the moment, though, Sans was filled with joy, and big blue tears welled up in his vision as he moved to sit right next to (Y/n). “(Y/n), look at our little girl,” he said, his grin broadening into a smile that threatened to crack his skull in two as he held up the tiny skeleton. “Look at the beautiful little girl we have now, she’s adorable and she’s perfect, and, and-” Sans started to cry, cuddling his baby to his chest while placing kiss after kiss all over (Y/n)’s face. Papyrus soon came in afterwards, bringing paramedics in to check on (Y/n) and the newborn skeleton. The paramedics gave Sans a blanket to wrap the baby in, and brought all three of them into the ambulance to take them to the hospital for a proper check up. (Y/n) cuddled up to the baby as well, also crying tears of joy and placing delicate kisses on their daughter’s forehead. “So what are we going to name her?” (Y/n) finally asked, wiping at her face with her free hand. Sans planted a kiss onto her lips, then another one on the top of their daughter’s skull tenderly. She was already making soft noises at them, waving her fists around and cooing softly as the ambulance moved towards the hospital, the precious thing. “Varela Parisienne Gaster,” he said, recalling the two favorite names they both had picked for a girl. (Y/n) smiled at him, then placed another loving kiss on their daughter’s skull. “Well, little Varela, you certainly chose an interesting time to come into the world,” she said fondly, receiving a soft gurgle in reply. “But we still will love you with all our souls.” “And you will forever be protected by your magnificent father,” Sans added, posing even though Varela couldn’t see it. “My two sweet girls, (Y/n) and Varela… I love you so much, and nothing is going to take either of you away from me again. I will be the best protector and friend and mate you will ever have.” (Y/n) shared another kiss with him, grateful for his promise and for the fact that the paramedics had given them what privacy they could. Sans knew that he had to protect them both, but it would be an easy task. After all, he was the Magnificent Sans, and nothing would be too difficult for him, especially if it came to his lovely little family.