John notes the yelp with some amusement, but most of his focus is on what follows: the tipsy little laugh and breathy affirmation. Excellent. He'd been proceeding with more caution than his smug facade had suggested — better to err on that side than cause Martin any actual pain, which John wouldn't want to do even if it was what Martin was asking for — but it sounds as if he got it right. It's rather in keeping with Martin's other requests, really: the illusion of captivity, the suggestion of helplessness. Except that this is much easier on the wrists.

He isn't sure he wants to apply any more pressure on Martin's hair than he is already, but he also knows that Martin's awaiting some form of escalation, and he doesn't want to disappoint. Fortunately, their current configuration offers plenty of options — and there's more than one way to interpret the way Martin tips up his chin in implicit offering.

John grins, boozily mischievous, and gives Martin's neck a light nip. A little goes a long way in this regard, as he's already learned, and he keeps things gentle until it occurs to him to wonder just how far a lot would go. There are no conscious calculations; he simply chases an impulse, one that naturally combines things that he knows Martin likes without sliding into any uncomfortable extremes. He doesn't bite down, he just closes his teeth around a portion of Martin's skin and sucks in, harder than usual, his cheeks hollowing. He can only maintain the pressure for a few seconds before he has to ease up, largely because he's fighting back a smirk and he doesn't want to produce any accidental raspberries.