Early on, they had agreed to a list of things that were Not Okay. Sex in public places, especially pools. PDA that went beyond hand-holding, hugs, and/or chaste kisses. Sex without protection because, even though they had both been virgins, it is the Responsible Thing to Do. Heavy metal music. Okay, so that has nothing to do with sex, but say it came on the radio or something during...and yeah, they'd have to stop, full stop. Sex with clothes on that they could not bear to sully. Hickeys, for obvious reasons (his dad eyes them like a hawk, along with half the Glee club, and Kurt bruises like a peach and he is so serious about his skin care regimen that it's become part of their relationship, hello, and besides that, see: trashy).
Of course, Blaine isn't really thinking about this last one when they make out. It's not that he intends to break one of their Rules; he's just getting into it. Making out has become something that he has become enthusiastic about because--well, it's all they do. Kissing and nipping and licking take on a whole three-dimensional world of their own when they are the beginning middle and end of any given encounter. He's become a master at changing it up, at using his tongue and teeth to great effect without freaking Kurt out, at knowing just where his hands can go and for how long.
The problem is that Kurt is just so damned unknowingly sexy that he forgets to put the breaks on sometimes. Kurt may claim to know nothing about sex, but he's obviously out of touch with how natural he can be when they're making out; the little noises he makes, the way his body melts into Blaine's, the way his skin flushes and his eyes go dark green and his pupils blow wide open and how his fingers close around Blaine's back or shoulder like a vise, and the way his hips rock into Blaine whether he's on top or on the bottom or they are side to side.
So Blaine forgets himself. And he latches onto a patch of Kurt's throat, the spot just above his clavicle, and sucks. And keeps sucking, because Kurt is whining and pressing up into him. It's only when Kurt pulls away that Blaine sees the huge purple-red bruise ringed with spit that he's left on Kurt's skin.
"Blaine," Kurt sighs.
"Crap," Blaine replies. "Sorry. Got distracted." He rolls them onto their sides and pets a hand down Kurt's back. "I still have some of that concealer that you left here--"
"It's, um, okay, we can just," Kurt sputters, and glues their mouths back together.
Blaine certainly isn't going to argue. He hums happily into the kiss and then goes back to exploring Kurt's neck and shoulders (Okay Spots), avoiding the buttons on his shirt (undressing is Not Okay) and keeping his hands at the small of Kurt's back (the ass is is also Not Okay yet). His eyes are closed and so he doesn't really process that he's kissing over the hickey until Kurt makes a strangled, dying noise.
He stops. His lips are just brushing the edge of it. Kurt is shaking underneath him. Daringly, he kisses the hickey. Kurt whimpers.
He wants to ask. He wants to say something, but it's so monumentally awkward. So he picks a spot on the opposite side of Kurt's neck, a little higher up, more towards where it meets his shoulder, and he closes his lips around a patch of skin and pulls until he feels Kurt's body twist and push down against his. He knows that it must hurt, but Kurt isn't stopping him. When he pulls back he eyes his handiwork, smaller than the original but still very pretty, all reds and pinks smeared like paint over Kurt's creamy skin.
He'd never thought about it that way before, but the marks are beautiful in a kind of twisted way.
He licks across the fresh one, and Kurt gasps.
He has to say something, this is--
Kurt rolls them over and straddles Blaine's right leg. He's hard.
Blaine fists his hands around the back of Kurt's shirt. "Honey? Talk to me."
"Don't stop," Kurt breathes.
Blaine's brain fizzles. They are rapidly going off of the Okay grid into places unknown. But the--god, Kurt looks amazing covered in mouth-shaped bruises, and Blaine did that, and he wants to keep doing it, Jesus. He kisses over the older mark, drawing on it lightly, experimentally.
"H-harder," Kurt moans.
Blaine is already rock hard in his jeans, but at that he throbs, feeling pre-come slide down the head of his cock. Kurt rocks into his thigh, equally turned on, and oh, Jesus, Jesus Christ this isn't going to last very long, is it?
Blaine takes a risk and slides his right hand up the back of Kurt's shirt. His skin is on fire. Blaine groans, tracing Kurt's spine all the way to the back of his neck.
He sucks at the marks, hard and fast, and creates a few quick, smaller ones, all over Kurt's throat and neck. He scrapes his fingernails down Kurt's spine, and Kurt bucks against him. The outline of his cock is fully formed know, and Blaine can feel the hard squash of it between two layers of clothing.
"Do you want to--" he begins.
"No," Kurt gasps, spine bending under Blaine's fingers. "No please just--keep doing that and--bite, maybe?"
Oh my god.
He bites at the bruises, feeling Kurt buck and twist. He sucks, darting from mark to mark. But Kurt always nudges him back to that original one that he'd made thoughtlessly, so eventually he latches onto it and just keeps drawing on it and biting it.
There's no denying it now; Kurt is humping his leg with every intention of coming. Blaine is frozen by the thought. It's so hot. It's so unexpected.
He bites everywhere he can reach, and then he cups Kurt's jaw and starts pressing his thumb into the bruises where he can reach. And then he puts his free hand back under Kurt's shirt.
"Blaine," Kurt moans urgently. He's panting.
Blaine feels kind of out of his depth; he's never seen Kurt like this before, loose and aroused and right there. He alternates kissing and pressing the hickeys until Kurt is shaking.
"I'm close," he whimpers, and Blaine--
Blaine comes in his pants rutting against Kurt's thigh, he can't stop it. He feels like he goes blind for about ten seconds, and then he just keeps dribbling into his underwear, gasping for air, and he claws his fingernails up Kurt's spine hard enough to draw red lines, and Kurt sobs and bends in half and rides his leg into the mattress and comes against his jeans, crying out.
"Kurt. Jesus, Kurt."
"Have to change the list," Kurt gasps. His neck and shoulders are literally covered in hickeys of varying sizes, colors, and depths. Blaine's cock twitches weakly.
He kisses Kurt, rough and wet, and rolls him over onto his back, mapping each bruise in turn, until Kurt is gasping and writhing under him again.
"Again?" Blaine asks breathlessly, thrusting their hips together.
"Oh dear god please yes," Kurt whines.