Your name is Dave Strider and your best friend, Karkat Vantas, happens to be hot as hell.
It's your birthday; your 17th, actually, and he dropped by to give you your present.
Which, evidently, is sex.
It happened quickly, to the point that you're not actually even sure it DID happen. The two of you were in your room, playing one of the new video games your bro got you, when the conversation turned serious. Karkat is a troll―one of the many that immigrated from Alternia to Earth about 60 years ago. You met him in kindergarten, but didn't become friends with him until relatively recently.
He's a mutant blood; red, you've found out, cherry red. That's his blood color. You're a bit of a mutant yourself; red, you've always know, cherry red. That's your eye color.
Both of you grew up being tormented, spit at, made fun of. So you've both learned to hide your mutation; you wear dark shades, Karkat wears turtlenecks. He does everything he possibly can to keep his blood a secret, but he let you find out after you became best bros. He trusts you.
So he's talking to you, and you're replying, talking about how difficult it is, how much it sucks, and before you know what's happened, he's kissing you; gentle at first, slow and steady, his hands in his lap because he doesn't know what to do with them. And then you bite his lip and that's that.
He shoves you so you're laying on your side on the ground, rolled over with him flush against you, his hands gripping your shirt. Your own hands go to his hair, tug on the black locks, curly and soft, and he mewls somewhere in the back of his throat. You smirk a little; you like that noise, especially when you're the one making him do it. The troll bites your lip in response, and wow JESUS your lip actually BLEEDS. Goddamm trolls always have sharp teeth. You cut your tongue on them a little.
Feeling him smirk in return at your audible reaction, your hands wander over his horns, running over the smooth service with your thumb. You honestly weren't sure if he was going to react, but when your twisting slows down, he pulls away from the kiss, butting his head against your hands.
"What's the matter, Karks?" you ask as he glares at you.
"Hornplay this early on, Strider?" He says, but his voice is low and a little nervous. You blink; you hadn't realized that might've been a taboo or something. Actually, for the most part you hadn't realized it was that sexual in the first place.
"Uh..." you sit up and scratch the back of your neck awkwardly. "Sorry, I guess."
But Karkat just rolls his eyes and huffs. "Well now that you've started, you have to either keep doing it or make me leave, douche bag." And then he's kissing you again, and you melt into him much to your embarrassment. When you don't push him away, he guides your hands back to his head and sets them near his horns. You start playing with them again.
He actually fucking purrs―like a fucking cat. You love it, your tongue slithering into his mouth and your hands working harder to make him do it again.
It takes a while, but sooner or later you have him mewling for you to continue, so you smirk and drop your hands from his horns to his pants, fumbling to unbuckle them. Your own dick is twitching to be played with, but you thrust your hands into his underwear anyway, not really knowing what to expect.
Trolls, you find out, have fucking tentacles. Kind of.
They look vaguely dick-ish, except they slither and coil and are much slicker than the human penis. But Karkat is still making those little noises, and he's saying, "No, idiot, my nook, my nook," and you furrow your eyebrows in confusion.
He groans. "Don't tell me humans don't have nooks."
"Nah, just pussies and dicks, man. What the hell's a nook?"
Just as the question leaves your lips, he grabs your hand and pushes it past his bulge-thing, where you can feel the folds of a...vagina? Something like that. "This," he says, his voice in your ear, "is a nook."
He shivers when you trace your fingers along the entrance, and instead of asking questions, you continue doing that until you find a place that makes him grip your shoulders harder, panting, and continue with that.
"Chicks have, uh, nooks, by the way," you say, "humans just have one or the other."
"Sh-shut up," he mumbles; it's probably supposed to sound commanding, but his voice quivers and it just sounds hot. "K-keep doing tha―fuck!"
"S-sorry," you say, nervous. In all honesty, you've never had to play with a vagina-thing before; it's not that you're a virgin, you've just only had male, human partners before. Karkat would be the first troll, obviously.
"No, dumbass, that..." he leans his head against your shoulder. "Just keep doing that, what you're doing right now."
Fuck, he's grinding against your hand. Fuck fuck fuck.
"Hey, it's my birthday," you mumble, "and as hot as this is, my cock's in need of some attention, so..." you attempt to unbuckle your own pants with one hand.
You think he rolls his eyes. "H-hold on," he says, "I...hold on..."
"What?" you snap, a little irritable because you're fully hard and horny as fuck and he's asking you to wait?
"You...you can fuck me," he mumbles against your shoulder, "if you want. Instead of just using your own hand or some shit."
And that sentence goes straight to your dick. "Fuck."
"I," you lick your lips, "yeah, th-that...yeah."
He smiles a little, his fucking overbite showing and for some reason you think it's cute as hell, and you take your hand from his...nook, and get up, locking the door in the sudden realization your bro could've walked in.
When you come back, you push him down onto your bed and slip your shirt over your head, his as well, and run your hands over the scars on his chest, leaving hickeys down from his neck to his belly button.
"S-strider, just get on with it," he says.
You glance up at him from where you're kissing his stomach. Your shades had been taken off along with your shirt. "Only if you beg."
"Don't be so loud," you say, because your bro is downstairs. "And you heard me."
He's still panting from the previous events, his eyebrows drawn at what you said. You nip at his skin.
"F-fine," he grumbles, covering his eyes with his hands. You lean up and pull his hands away.
Again a mumble.
"Couldn't hear you, Karks."
"Fuck me already!"
You smirk. "That's more like it."