Alec being in love with him turns out to be the longest, most involved bit of foreplay Jace has ever been involved in, spread out across years.
In the end, Jace breaks.
“If you get on your knees I’ll slide my dick down your throat,” Jace hears himself tell Alec, without consciously knowing he’s reached his limit and is done now.
Alec swallows convulsively — again, the exact action that made Jace hit his limit — and turns to look at him, startled and wide-eyed.
“You heard me,” Jace says, before Alec can ask him to repeat himself or go ‘What?’ or whatever it was he was about to say.
Alec slides down on his knees, eyes still wide and locked on Jace’s face.
Jace doesn’t bother with more foreplay, because Alec has been the world’s biggest and most available tease when it came to Jace for half their lives, just unzips his jeans and slides his dick into Alec’s mouth, one hand in Alec’s hair.
Fuck, Alec’s mouth is hot and wet and nothing but a slick glide, even when Jace hits the back of his throat, and Jace doesn’t stop Alec’s mouth is pressed against his groin, both of them moaning.
Jace had learned about Alec’s lack of gag reflex a few years back — and hadn’t that added another level of burn to what Jace had to deal with between them — but knowing it first hand was completely different.
Alec’s hands are wrapped around the back of Jace’s thighs as Jace slides back out of his mouth to fuck back in, throat opening up around Jace’s dick like he was made for it.
Either for sucking dick, or for Jace — Jace hasn’t decided yet.
Jace isn’t interested in taking it slow or taking his time — they can do that the next time, or the time after — just fucks Alec’s mouth, the way Alec has been fantasizing about for years.
Alec has no fucking idea how loud he’d broadcasted that fact to Jace, every time they were together. Jace’s hold on his self-control has been steadily slipping since he was sixteen.
It’s good — if Jace hadn’t already planned to continue doing this, he’d be mourning the fact that Alec just ruined him for anyone else; no one’s ever going to compare favourably when they’re being compared to Alec — and he isn’t going to last, but that’s fine, because Jace is almost entirely certain that Alec is going to come when he does.
He stills, dick all the way down Alec’s throat, and orders “Swallow.”
Alec does, moaning desperately, and it’s so good Jace has to lock his knees.
“Fuck,” he hisses, tugging on Alec’s hair, earning himself another moan. “Again.”
The order is unnecessary. Alec keeps doing it, gagging himself desperately on Jace’s dick now that he finally has it, and dear fucking angel, Jace is an absolute idiot, because he could have been having this for years.
“Fuck, Alec,” Jace says again. “Later, I’m going to spread you out on my bed and fuck you until you scream.”
Alec comes. Shuddering and moaning and swallowing around Jace’s dick, and Jace comes too, how could he not? His grip on Alec’s hair is probably too tight, but Jace knows enough about Alec to know that he loves it.
And then he ends up having to pull out of Alec’s mouth himself, because Alec seems perfectly content to keep Jace’s softening dick in his throat.
“If you try to fuck someone else while you’re fucking me I’ll probably kill them,” Alec says, voice hoarse.
The combination of the threat and what Alec’s voice sounds like right now makes his dick twitch.
“I’m not going to fuck anyone else,” Jace says. “Neither are you.”
Alec shivers and presses his face into Jace’s hip, near their rune, and Jace lets go of Alec’s hair so he can run his fingers through it, instead.
If Alec thinks Jace is letting him go after all he’s put Jace through, after Jace picked him twice, he’s delusional.
And the next time someone looks too long at Alec, Jace will probably kill them.