Probably a good thing that John isn't trying to push him away, because at this point the only way to stop him is to bite down on his dick, and he'd rather avoid that. Gagging or tears he can live with. Actually, the more of a mess he makes of John, the better.

Which is why he doesn't let up even a little. With that willing mouth, he sees no reason to, and he tilts John's head just so, allowing him to push in deeper and harder with each thrust, each time pushing the swollen head past the tight rim of his throat, until he's balls deep in his mouth each time. He's not gonna last that long if he keeps up the pace, but this is a quick screw while they're stuck on a lift. He'd rather get off fast before they start moving again. "Come on, come on... yeah..."