Posted originally on the Archive_of_Our_Own at https://archiveofourown.org/ works/2320688. Rating: Explicit Archive Warning: Underage Category: M/M Fandom: Teen_Wolf_(TV) Relationship: Derek_Hale/Stiles_Stilinski Additional Tags: Bodyswap, Fuck_Or_Die, First_Time, Kidnapping, Magical_Healing_Cock, Werewolf_Mates, Knotting, Bottom_Derek, Buzz_Cut_Stiles_Stilinski, Season/Series_02 Collections: Anonymous Stats: Published: 2014-09-17 Words: 2845 ****** Switch It Up ****** by Anonymous Summary Stiles has a concussion. Derek's dick saves the day. Notes WARNINGS: consent maybe a little dubious because of context? also, no condoms because werewolves. :D SATURDAY, 12:30 AM "Oh my god, I almost died," Stiles says, toppling through his window onto the floor. He spent a full minute with one hand clinging to the sill outside and the other trying to slide a claw beneath the window and the frame. At least he never leaves it latched. "Also, you know that you have no cover out here, right? I mean, your ass does, I guess." "Your next-door neighbor is still angry with your dad about the property line dispute from 2002, she's not going to tell on you," Derek says groggily. He's lying on the bed with Stiles's laptop, looking perfectly comfortable in Stiles's pajamas, in Stiles's body. Ugh. Gingerly, Stiles retracts the claws before he punctures something, like himself. One of him, whatever. "How do you even—no, I don't want to know. Did you find anything out?" Derek shakes his head, then winces. Oh, yeah, head injury. "You?" "Deaton says he doesn't know anything, and Peter definitely knew I wasn't you." At least, Stiles hopes that's why Peter was all up in his personal space as he denied all knowledge of the witch's presence in Beacon Hills, let alone her purpose. Add that one to the list of reasons Stiles should be in therapy forever. "I told you he would," Derek says as he shuts Stiles's laptop. "And there isn't anything about this—" He gestures between them. "—on Yahoo!." "I can't believe that no one ever wanted to test drive a werewolf dick and thought this would be the easiest way," Stiles says, tossing Derek's leather jacket over the back of the desk chair. "Also, seriously, Yahoo!? Is your default browser IE6?" There's a suspiciously long pause before Derek says, "I don't have a computer right now." Stiles sighs and holds out his hands. "Gimme." Derek surrenders the laptop. When Stiles sits down in his chair, Derek's jeans ride up and dig into his balls. Maybe seriously questionable fashion choices are part of Derek's martyrdom quest because Jesus, this can't be healthy. "Are these pants even your size?" he says after a moment. "I'm taking them off." Derek rolls over and sticks his face in Stiles's pillow, which, whatever, it's not like Derek doesn't see his own naked body all the time. For Stiles, it's a brand new experience. He gives himself three seconds to stare at Derek's dick—huh, maybe he's a grower, not a shower—before he yanks on his loosest pair of sweatpants. They cling about as much as the jeans do, but at least they're comfortable. It takes Stiles exactly four minutes and fifty-six seconds to figure out what the spell is, because he's using Google and Google's creepy customization of his search results is sometimes a little too helpful. "This isn't about your junk," he says. "This is supposed to be some kind of spiritual journey for werewolves. You take a walk in human shoes and switch back when you're done learning a valuable lesson about humility." "'A valuable lesson about humility'?" Derek says incredulously to Stiles's pillow. Stiles shrugs. "Maybe she got mad about Isaac insulting her shoes and you were the nearest target?" This isn't as awkward as he thought it was going to be when they split up this afternoon. It's like Derek never jerked him off at all.   FRIDAY, 4:30 PM "I can't believe I'm missing lacrosse practice for this," Stiles groans as he fumbles his way back to consciousness. He's kind of woozy, but his head isn't throbbing. "Why doesn't my head hurt?" "I'm taking your pain," Derek says. "Do you—I don't know what to do for a concussion. Am I supposed to wake you every hour?" Stiles says, "Fuck if I know, I have a concussion." He squints at the dim room around them. Great, he loves being kidnapped. The last thing he remembers is getting dressed this morning. He's still wearing the socks, but they took his shoes. Assholes. "Who do I have to thank for the brain damage?" Derek says, "There's a witch—" which is right around the time Stiles tunes him out and goes back to sleep. He wakes up a little later to Derek shaking him. 'You don't look good," Derek says. "They took our phones. I don't think the pack can hear me howling from here." "Wow, I slept through that?" Stiles says. Derek must not be pulling his pain anymore, because all of the sudden, his head hurts, his side hurts, and one of his wrists is definitely sprained. Or broken. When Stiles reaches up to touch his head, Derek catches his hand. "Don't do that." There's blood on Derek's hand; there's already blood on Stiles's. Stiles doesn't remember that. He doesn't— "Oh," he says. "This is bad." Derek bites his lip. "There's something I can do. If you want." "Are you going to heal me with the power of love?" Stiles says. "No," Derek says, glaring.   SATURDAY, 2:30AM When Mom was dying, Stiles sat at her bedside a lot. To keep her company, when she was awake, and to be there if she woke up, later, when it happened less often. Sitting up with Derek in his bed feels uncomfortably like that, multiplied by the out-of-body experience that is being out of his actual body while Derek's inside of it. He has his hand on Derek's forehead, because that's the least weird way Stiles can think of to draw the pain away. It makes Stiles feel kind of queasy. Probably Derek should have gone to the hospital, after, but Derek told Scott he felt fine and Stiles went off to try to fix their newest problem and not look Derek in the face. His face. Stiles didn't really think it through, the part where Derek heals major injuries all the time and probably thinks a lack of gaping wounds is sufficient to go home and try to sleep it off. Stiles has been googling internal bleeding on his phone with his free hand for the last half hour. The results are not promising. Softly, Stiles says, "Hey." When Derek doesn't respond, he pokes Derek's shoulder. "Dude." "Don't call me dude," Derek mutters. "Yo, sourwolf, do you think I can heal my body with your dick?" Stiles says. "Because I think one of us might be slowly dying, and it's not me." All of the sudden, Derek goes from zero to awake, which, wow, this must be what Stiles looks like when he realizes he's slept through his alarm clock again. "What?" "It's that or you have to deal with my dad and multiple medical professionals when I take you to the emergency room," Stiles says. "I'm not sure how you're going to convince them you don't have a serious head injury when you still have a mild head injury and you're not me." Derek gives him a somber look that's out of place on Stiles's face. "This isn't—before, I did that to save your life." Stiles sighs. "My life, not actually saved, also partially yours right now, so…" Derek just stares at him for a moment. "Look, my body is definitely capable of appreciating your abs," Stiles tries. "And who hasn't thought about boning themselves from an alternate universe? I can deal with it." Derek stares some more. After a moment, he says, "I have never thought about having sex with myself from an alternate universe."   FRIDAY, 5:00PM It takes Stiles a long time to get hard, possibly because of the major blood loss. This seems like a really strange trait for werewolves to have evolved, like: sexual healing? Wouldn't on-demand healing by touch be easier, like Jesus? He wants to say this to Derek, but his mouth isn't working right, so he just watches Derek's hand wrapped around his dick, stroking him to arousal, and jerking him off. Maybe this is how Derek jerks himself off. Maybe Derek is into guys. Stiles doesn't know. His orgasm takes him by surprise. For a couple of seconds, he thinks he's dying, because this is a light-at-the-end-of-tunnel orgasm, fireworks and electricity, the kind of orgasm that Bernini put on the faces of saints, okay. Then his vision gets a little bit less hazy, his breathing more regular; he can feel his side start to knit together. "Wow," Stiles says. "Um." Derek tucks Stiles's dick back in his pants about two seconds before the witch slams open the door to their prison and says, "Well, well."   SATURDAY, 3:00AM It's a good thing Dad is working the night shift, because this is noisy. Is Stiles normally this noisy on his own? Does he make the bed creak this much? All he's done so far is get lube out from under the self-love shoebox under the bed. Belatedly, he says to Derek, "Have you ever done it like this?" "Not in someone else's body, no," Derek says. Stiles rolls his eyes. "Look, you have a human butt now, I'm just saying—it's probably going to be different." Man, Stiles isn't even going to be in his own body when he loses his virginity. That sucks. Maybe he can be a born again virgin? He'll have to google that later. "Great, probably. I know my butt pretty well." Derek huffs. He's lying on his back, which seems like it'll be the easiest position in which to bone. Poor body. Stiles isn't sure whether or not he's more sympathetic for Derek or himself. "Just get on with it." "Fine," Stiles says. "Do you want to make out first or something?" "Why?" Derek says. Stiles debates saying something about Derek's sad, sad life and decides against it. Usually he likes to give himself a little warm up, pluck at his nipples, tease at them with spit-damp fingers, but if Derek does not want tender loving, Stiles is going to respect his boundaries. The internet says that's important. "Can I put my mouth on your dick, at least?" After a moment, Derek says, "Yeah, fine. If you want." "I've always wanted to give myself a blowjob," Stiles says wistfully, and then he goes for it.   FRIDAY, 5:30 PM "Your pride is an embarrassment," the witch says to Derek. "What do you think your mother would say about your behavior?" Stiles glances over at Derek, because, yeah, he's kind of curious what Derek's mom would think about him giving underage teenagers life-saving handies under duress. Derek's face unfortunately gives no clue. Derek says, "Don't talk about my mother." The witch ignores him. "I want you to think about your actions, young man." She flicks her fingers and then, she's gone. "What the hell," Stiles says to Derek's claws. That are now Stiles's claws. Just like Derek's hand is now Stiles's hand, complete with Stiles's jizz drying on the palm. "What the hell." "We should get out of here," Derek says from Stiles's body, which—okay, Stiles can see why Derek was concerned, because there are dark patches of blood on his faded red hoodie and a long, crusted smear from temple to cheek on one side that curves into a slice across one of his cheekbones. This is not going to be fun to explain to Dad. Stiles does kind of wish he could get photos of the ensuing bridal carry, though.   SATURDAY, 3:10AM Sucking his own dick always seemed exotic and taboo, as well as more efficient than trying to find a partner who was into it. This was not really how Stiles thought it would go, though, back before he realized there were limits to his own flexibility. "My jaw hurts," he says, pulling off and rocking back on his feet. "Does it normally take this long?" "I don't know, it's your body," Derek says. Maybe it's Stiles's imagination, but he's looking a little better already. He seems a little steadier on the edge of the bed. Stiles rolls his eyes. "I've never had a blowjob before, how would I know?" An awkward silence descends. "I'm sorry, it's difficult to—" Derek frowns. "I'm injured." "Hey, I managed to get it up for you while I was dying." Stiles says. He's still holding his own half-hard dick. At least Derek's not getting any less hard. "Do you need to lie back and think of Erica or something? I'll probably recover from the wound to my ego this decade." Derek gestures at Stiles and the body that's more toned than a David Beckham for H&M ad. "You're not you right now." "I know," Stiles says appreciatively. "Thanks for the loaner eight-pack." "That's not what I mean," Derek says. Stiles eyes Derek skeptically. "Do you like me?" He's a teenager with a buzz cut and a big mouth. It's a little hard to believe. Like it's an answer, Derek says, "Smell me." "Dude, you smell like AXE," Stiles says, but he complies, leaning forward to sniff his… leg, sure. For a moment, all he gets is bodywash and a mild funk that's probably from his infrequently-changed sheet. Then his nose picks it up—the scent is faint, cinnamon and musk, but it makes his body tremble with conflicting desire and contentment. Wow, Derek has a literal werewolf boner for him. Stiles feels a little flattered, a little disturbed, and super aware of his dick. The one in his pants, not the one in his hand. "What is that?" Derek sighs. "You're my mate." Stiles glares at Derek for a moment before he says, "You told Scott that wasn't a thing." "I lied," Derek says. "It's why I can heal you." "With your dick," Stiles says. "With my—yes," Derek says. After a moment, Stiles starts stroking Derek's dick again. He has a plan now. A plan for (1) neither of them to die or (b) think about the long-term implications of werewolf mating, what the fuck, seriously. "Okay," he says to Derek. "So what do you think about when you jerk off? Do you thinking about biting me? Do you think about me having your—puppies, or whatever?" "Um," Derek says. "People are into weirder stuff," Stiles says reassuringly. He's watched enough hentai to know. "Trust me. Unlike you, I know how to use the internet for porn." He nudges Derek back on the bed until he's lying on his back, Stiles propped up on his elbows above him. "What I am I doing, when you're doing me?" Derek's quiet for long enough that Stiles is afraid this isn't going to work. Then he says, "I like it like this, with you under me. You're—loud. I'm not." "Okay, pretend you're me," Stiles says. "Pretend you're my mate, and I'm going to—knot you. You're excited about it. I'm going to make you loud." He drizzles some lube over his fingers, reaches down between Derek's legs where he's hot, tight. Starts fast, two fingers, like he always does—Stiles wishes he was in his own body, could feel how good this felt. But it's good like this, too, with his dick heavy and hard between his legs, brushing against Derek's thigh. He leans down and breathes against Derek's throat, hot and wet, and Derek arches up against him. "Stiles," he says—whimpers. "Do you think of me? Like this?" Well, Stiles has never thought about them as werewolf mates, or swapped into each other's bodies, but— "Yeah, I do." Derek whines, high and tight, and Stiles turns his head to kiss him. He's not really sure how to do this, aside from the obvious initial stage of lip-to-lip contact, but Derek seems to. The kiss goes from chaste to dirty pretty fast, and right around the time Derek slips his tongue between Stiles's lips, he wraps his hand around Stiles's dick, and shit. Stiles's balls tighten. He wants inside Derek. Days ago, weeks ago, months ago, now. He shifts his hips, lines up, pushes in. "Oh," Stiles says, and then he can't say anything, he's just panting into Derek's mouth while Derek clenches around his dick, drags his nails up Stiles's back. Stiles can already feel his knot swelling. This is going to be over so fast, and he doesn't even care, because he's going to do it again and again, because nothing's ever felt this good. "Stiles," Derek says, gasp, and clamps down hard, milking Stiles's dick, the hottest, sweetest, most perfect feeling in the universe. "I want it, I want you—" Stiles says, "You got me," and knots him.   SATURDAY, 4:00 AM "Was humility taking it up the butt?" Stiles says. "I wonder if we'll ever know." It's nice being back in his own body now that it's devoid of life-threatening injuries. He feels really relaxed and comfortable, even though Derek's still tied in him and squashing his ribcage. Derek is also dead asleep. Maybe healing takes a lot out of him, maybe he's just living the dude stereotype of passing out as soon as he comes. Stiles is down for testing this theory. Stiles pets Derek's hair. "Want to see if this works for eyestrain?" Derek snores. Please drop_by_the_archive_and_comment to let the author know if you enjoyed their work!