What keeps him going? Constantine almost laughs at that, only keeping it to a wry huff to avoid throwing off all the delicate adjustments Bruce is making to his posture and stance. The man is precise and he's learned from past encounters that trying to throw him off often results in an even longer wait for what he desperately wants. Bruce also isn't above restraining him and leaving him to stew either, none of which is what Constantine feels like indulging in tonight.

So he keeps still, letting Bruce move him around with minimal protest, instead favouring a sigh of relief as it finally starts to head in the direction he wants and he's rewarded with the feeling of tightening straps and reassuring touches.

"You know me, sheer bloody-mindedness." He hisses, whole body twitching as Bruce drags nails over still sensitive skin and then manages to follow it up with just enough contact to be nowhere near enough.

Another crisp thwack, and he unbalances enough for Bruce to push him firmly into the mattress and Constantine can't help but feel that Bruce can see through his answer just as easily as he can likely see how hard he's gotten from this treatment.

"Fuck, alright! Bloody tease." Even positioned as he is, Constantine rocks back as much as he can, seeking more contact. "I keep going because maybe one day, I'll be able to make right for everything I've done and failed to do. Or at least I'll die trying and then get what's coming for me.

"Now will you stop mucking about and start fucking me already?"