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Katsuki isn’t in the best mood when he’s stomping towards Endeavor’s office. He knows the only time he’s summoned is to be bitched at or given another assignment, and he just returned from one. Not even thirty seconds after stepping foot in the building, a shitty intern informed him of an urgent meeting with the guy. He couldn’t even shower off the grime from that last outing, not that he’s messy and walking around with blood and shit all over him, but it’d be nice to unwind. Regardless that it’s demons or rogue angels disrupting the balance between the worlds, he’s still assassinating them, and it’s nice to have a day or two to decompress. Skipping pleasantries like knocking, he kicks open the door with a scowl and stomps into the room. Endeavor scrunches his face in annoyance and quickly hangs up the phone. “The fuck you want me for, old man?” “Bakugou,” he warns in a stern voice that he doesn’t give a shit about, “that’s not how you speak to a superior.” He rolls his eyes, crossing his arms. “Get on with it.” Endeavor sighs, pinching the bridge of his nose. “You have a new target.” “I just finished one!” “And you’ll have your break after you complete this one. It’s a rush job.” Katsuki scrubs a hand over his face, accepting his fate. “Who is it?” “A demon that goes by ‘Dabi,’ his murder victims are up to 30 and he needs to be eliminated immediately to keep the balance between us and the humans.” He keeps his expression neutral, the same look of haughtiness as he always has during these things, but his suspicions have been raised. Dabi isn’t a new name to hear, he’s actually met him on other assignments. The shady fucker isn’t exactly helpful, but he stays out of his way and throws insults from afar. While he is sleazy and sells drugs for cash and whatever other illegal shit, he’s never noticed him kill any humans. Dabi isn’t cruel, not in a way to be a mass murderer. Katsuki could be wrong, but he likes to think he has a well enough read on the guy since they’ve exchanged blow jobs and handy’s enough times. “Do I get a file?” Endeavor clenches his jaw, suddenly stiffer than before. “No, there’s not enough information to have one. We do know he’s somewhere in Musutafu.” That’s a load of shit. He’s gotten some with barely a known alias. There’s something off about this whole thing, and if it wasn’t for his – personal – involvement with Dabi, he’d tell the captain to shove it. But he kinda wants to keep the asshole safe – ugh – and the best way to do that is to take the assignment himself. “Whatever. But when I get back, I’m not taking anything new for two months!” He stomps out of the office and heads toward his room in the living quarters. He makes quick work of a shower and changes, opting to throw on his more human-like clothes, dark jeans, and tucks a plain black t-shirt in his back pocket. The other angels turn their noses up at it, but he doesn’t give a shit. He knows exactly where to look for him, and doesn’t plan on fucking around with a glamor. The flight down to earth is uneventful, and he carefully lands somewhere and folds his wings inside his back. He pulls the shirt over his head and pivots to the right, down one of many streets toward Dabi’s debilitated apartment building. None of the few people he came across gave him a second look as he picks his way through the disgusting hallways. There is filth all over and he won’t be surprised if rats were living in the walls. He’s never understood why the guy chose this place to live, any other demons he’s encountered used a variety of methods to live in well off areas. Katsuki had never been here before now, but after a lewd proposition one day, he at least knew the address. He makes it to Dabi’s door and bangs on the wood. There’s no response, but he hears rustling and waits thirty seconds before he knocks even louder. A dull thump hits what he assumes the floor and a quiet curse drifts through the door. Another thirty seconds pass and Katsuki bangs his palm hard on the door again. “Oi! I hear you in there, open the fuck up!” Finally, it swings open and an uncoordinated Dabi stands in front of him rubbing at one of his eyes. He’s in his demon form and it’s startling seeing it for the first time. Beyond tucking their wings back into their bodies, angels lack a separate form, they simply use a glamour that shields them from humans perceiving them if they want to stay hidden. Demons, on the other hand, physically switch forms to hide amongst the humans. Short purple horns jut out of his forehead, near his temples. The color matches the whimsical like rune-like markings under his eyes and jaw, and his arms upon further inspection. He still has the triple set of small hoops on his now pointed ears, eyebrow piercing, and nose studs. The same turquoise eyes level a bored glare at him. The white hair is shocking, Katsuki’s accustomed to black. “You done gawking now, kitten?” The corner of his mouth curves playfully, but there’s a ghost of anxiety behind his eyes. “Do you just open the door like this for everyone?” Dabi rests his forearm on the frame and tilts his head with amusement. “I probably could. Everyone here is a bunch of drug addicts and would just assume they were tripping balls, but no. I don’t. I figured since it’s you, I wouldn’t need to put in the effort.” “Just let me in already? This hallway is a fucking pigsty.” Dabi rolls his eyes, but moves out of the way to walk further into the room, which gives him an eyeful of a dainty tail flicking back and forth. Katsuki steps inside and slams the door shut. While no one can change how old and generally shitty the place is, the room is at least neat and tidy and free of most smells. “Alright, kitten, what brings you to my humble abode?” He hovers by the window and lights a cigarette and Katsuki notices webbing connecting his fingers at the midway point. “Why the fuck is Endeavor sending me to murder you?” There’s a sharp intake of breath, and the cigarette pauses inches away from Dabi’s lips. “I am a demon. Your little angel gossip filters through to us peons down below and I know how zealous he can get. Maybe he’s decided to purge the earth of all of us.” “Drop the act, princess. He would have spouted some shit like that cuz he likes to hear himself talk. He decided to lie and say you’re a mass murderer.” He chuckles dryly. “What makes you so sure it’s a lie?” The question echoes in his mind, because Katsuki’s been avoiding the answer. Whether it’s the truth or not, he still wants to protect Dabi. He’s a piece of shit, but he’s seen him go out of his way to help human children on the streets, and has patched Katsuki’s wounds up countless times. The admission is overwhelming. He’s never been naïve enough to believe everything is black and white, but there has to be a line somewhere, and he’s pretty sure siding with Dabi right now should be it. “Fine. What if it’s the truth? They were probably a bunch of shitty humans anyway that went unnoticed.” Dabi’s eyes widen a fraction and he takes a long drag of the cigarette. His hand shakes just the slightest when he flicks the ashes outside. “That doesn’t sound very angel like of you.” His face pinches up in a scowl. “I kill for my job, moron, does that sound ‘angel like’ to you?” A loud barking laugh fills the room. “Does anyone actually know what being an angel is supposed to be like?” There’s a hint of old pain in Dabi’s voice and a haunted flash of something crosses his eyes. “Dabi, what’s going on?” The tail twitches, and Dabi smothers the butt on the window sill. He walks closer to Katsuki, and he can’t help but feel like he’s being stalked like prey. He keeps still as Dabi grazes a knuckle down the side of his neck. “Do you talk this much before you kill your other assignments?” “Most of the time, they don’t even know I’m there. I’m not killing you, shithead.” His hands dart out to yank Dabi closer by the front of his shirt. “So just fucking tell me what’s going on between you and the old man.” His breath hitches a little and Dabi presses their foreheads together, allowing Katsuki to pick out the nuanced shades in his eyes. “You gonna be a good little angel, and save me?” The tone is mocking and insensitive, but Katsuki’s finally gotten a grasp on him and detects the underlying sound of hope. “Yeah, idiot, so explain to me what the fuck is going on!” he seethes. For a split second, Dabi’s expression is a swirling void of pain, fear, and anger, and Katsuki thinks he’s won. It suddenly morphs into his classic smug attitude, and he loops a finger in Katsuki’s belt loop to bring his pelvis flush against his. “Did you know my dick is different in this form?” The obvious avoidance tactic pisses him off, and Katsuki scowls. “Cut the shit. Are you that scared you can’t even say it out loud?” he taunts. His turquoise eyes burn with a flash of anger, and Dabi crosses the room to slam him against the wall, digging sharpened talons into his chin to force his face upward. “Leave it alone. It doesn’t even concern you.” “Like hell it doesn’t!” he hisses, throwing his arms out to bunch the front of his shirt into his hands to yank him closer. “I became involved when the fucker ordered me to kill you!” Katsuki can’t place the new blaze of emotion in his eyes, something like determination and acknowledgment, before he’s crashing his mouth into his. He’s always had shit track record with the shifty demon, craves his touches just as much as Dabi desires it. He’s seen with his own eyes the destruction of his fire, can feel the heat of his skin from it, but contact with him is always a soothing balm that Katsuki consistently leans into. Dabi’s lips are demanding and impatient, they steal his breath and force their own into him. The slightly dry skin molds his to their whim, and Katsuki blindly follows. It’s clearly meant to distract him, and he’s utterly weak for it and willingly gives in. Tip of his forked tongue teases his bottom lip and Katsuki lets it in to flick over his teeth and the inside of his cheeks. The hand formerly holding his chin slides to cradle the back of his head, angling it for a deeper kiss. The slender tail wraps around his thigh, and it surprises him that there’s enough strength in it to lift his leg up, to let Dabi slot himself closer. Their semi hard erections grind into each other, and Katsuki moans. The demon’s grin presses against mouth. “Already getting worked up?” “Fuck off!” He snickers and slips a hand up under his shirt, the fabric bunching together to give him room to roll a nipple between his fingers. Katsuki shudders, leaning into the pressure on his chest. Dabi breaks the kiss, leaving a wet path to his ear. “You think you can keep me safe, little angel?” It’s more of a whispered plea than a cruel taunt. Deft fingertips skirt over the button of his jeans. “Are you gonna let me inside you this time?” He’s hot and cold with his words, one minute a desperate prayer, and the next a sultry tease, and Katsuki’s struggling against the whiplash. “If it’ll get you to talk, sure,” he grunts, as if he would have said no otherwise. Sharpened fangs scrape across his jaw, and down the side of his throat until he ends at his collarbone. The flare of pain from Dabi biting into it causes him to moan and buck into the hand groping his crotch. It’s taken as an invitation, and a flurry of movement leaves him with his cock out and Dabi leisurely stroking it. There’s no wall behind him, and Katsuki clings to his biceps to steady himself. He’s abruptly lifted into the air and deposited onto the bed with surprisingly clean smelling sheets. He cooperates, with Dabi peeling his clothes off, and doesn't have time to feel self conscious about being fully naked in front of him before his nipple is taken into a mouth. Katsuki threads his fingers into the newly white hair and pushes him closer to his chest. The rational part of his mind argues that this isn’t what he’s supposed to be doing, but he’s been addicted to Dabi’s touch too long to deny even more of it. His chuckle vibrates through his chest and Dabi sucks on it with increased fervor. By the time he pulls up for air, both of them are red and swollen with a sheen of spit covering the multiple bite marks, Katsuki still whining from the loss of contact. “Easy, little angel, I gotta grab some lube.” He reaches over to the bedside table and retrieves a bottle, tucking himself between Katsuki’s legs on his stomach. “Oi, why are you still wearing clothes?” Dabi smirks up at him as he pours the thick liquid on his fingers. “I’ll do that later, now shut up.” He watches him brace his weight on an elbow and lick a stripe up the length of his cock, flicking that forked tongue across the tip to lap up the pre-cum. It makes his stomach clench and spine tingle, but he’s prepared for the heat of his mouth enveloping the head and slowly sinking down. This is something he’s used to, how Dabi curls his tongue around him and hollows his cheeks before swallowing him down his throat. Katsuki claws at the sheets, jerking his hip up, only to be held down by a palm on his lower abdomen. The tail wraps around his knee and tugs it wider. The first press of the warm lubed fingers to his rim is jarring, but Dabi keeps sucking his cock to distract him from the initial burn. His erection flags a little regardless, not until the two fingers have stretched him enough that it’s more pleasure than uncomfortable. Sweat makes his skin damp and sticky when Dabi crooks his finger and a shot of electricity lances through him. A low keen reverberates in the back of his throat, and he gasps as the assault to his senses intensifies as the stimulation to his prostate continues. Katsuki’s thigh gets pressed even closer to his chest by the tail and a third finger eases inside, scissoring him impossibly wide. It’s not even a dick yet. The pressure in his gut slowly builds and he can’t decide if he’d rather grind down on the fingers or thrust up into the throat constricting around his cock. The buzzing in his veins is overheating his body and turning his vision spotty. He’s right there on the edge and Dabi humming around him tips him dangerously close. Desperately, he tugs on his hair in an attempt to pull him off. “Fuck, you gotta stop.” Dabi’s eyes twinkle with amusement, and he drives his cock deeper, kneading the pads of his fingers into the sensitive nerves, and Katsuki moans as the pressure bursts, and he’s cumming. It’s only when he starts whining that the demon pops off and gives him a break. His hands shake slightly as he raises them to help peel the shirt off and toss it to the floor. His slim build is deceptive, and Katsuki can feel the toned muscles when he drags his hand down his chest and torso before pushing the waistband of his sweatpants down. The dick that springs free is… different. It’s the same shade of deep purple and longer than what it normally is. The head tapers to a point now, with a slight curve upward. The top and sides each have symmetrical lines of bead like bumps beneath the skin. The underside has a raised line with uneven ridges that slowly widen as it reaches the base. “That’s not gonna fit,” he blurts. The stupid thing is girthier too. “Oh, I’m gonna make it fit, angel. I’ve been dreaming about being inside your ass for ages.” Dabi drops a harsh kiss on his lips that has a lingering taste of his own cum. “Roll over baby, it’ll be easier.” Katsuki flips over with minimal help and buries his face into his forearms. A hand traces up and down his spine until he becomes more pliable. “Just like that, perfect.” Dabi curls a hand around his hip and the faint imprint of his talons brings him a level of comfort. Then the tip starts breaching him, and it’s fine – it's great – until the curve of the head pops through and the textured dick starts stretching him further. The bumps grind into his prostate and it’s paired with the burn in an odd combination that’s quickly going straight to his growing erection. But it’s a lot, and his lungs can’t inflate with air properly. “Fuck,” he pants. “How much is left?” “Half of it,” he responds in a strained voice. Katsuki groans from frustration and the dull throb of his prostate. He hears the cap of lube and more is poured onto his ass. Thumbs massage it into his rim, spreading it more open for rows of protrusions to ease inside him. An eternity passes before his hips stop flush against him, and Dabi falls forward to mold his chest over his back. “See,” he whispers smugly into his ear. “Told ya I’d make it fit.” “Congratulations, I feel your dick in my throat.” “You think that’s an insult, but I think that’s the first compliment you’ve given me,” he snickers. “Would you move and fuck me?” “Here I am, trying to be a gentleman and let you adjust.” “Gentleman, my…” He’s cut off by him pulling partly out and thrusting hard, punching what little air he had out of his lungs. Each roll of his hips works more of his cock in and out, slowly building up to only the tip remaining, and him driving back in. Katsuki’s skin is a large open nerve, and it’s like Dabi is branding his essence into him. He reaches back to claw at his thigh. “Flip me back over.” There’s a grunt of impatience, but he’s quickly flopped onto his back and bent in half for Dabi to bury his cock back inside him. There’s not a lot of space with his knees against his chest, but he manages to yank Dabi down by the neck to meet with an open mouth kiss. It adds more friction on his dick and he moans, licking into his mouth this time. Katsuki wraps his arm around him to bring their chests closer, and he splays his hand. He brushes his fingers over a scar on his back, and the placement, the shape, is undeniably from angel wings being ripped out. It has to be.Demons don’t have wings and this is a grotesque mirror image of his own wing slips. He pries his face away and gapes up at him. Weary turquoise eyes stare down at him, and he finally makes the connection of where he’s seen them before. “Dabi…” “Not now,” he rasps and dips back to resume their kiss, picking up a more frantic pace that makes his toes curl and back arch. It’s overwhelming, this new information, the cock filling every space inside him, and the firm pressure on own dick trapped between them. His mewl echoes in the room when he cums again, and he digs his nails into Dabi’s back and neck as he rides out the orgasm. It only takes a few more thrusts, and he’s cumming right behind him. The length inside him pulses with each wave of cum spilling into him, and it’s nearly painful on his oversensitive nerves. Dabi collapses from exertion, rolling onto his side to avoid crushing him. “My name used to be Touya.” Katsuki turns his head, still reeling, but catches the haunted glow in his eyes. “And I was a broken angel that my father deemed unacceptable to be part of his family. So he sent me away.” Dabi rakes his knuckle along his cheek. “Are you still determined to protect me, little angel?”