If there is a downside to using his mouth on Martin, it's only the fact that it generally means not being able to see the effect he's having. Much as he enjoys the myriad sounds he might coax out of him, being able to watch the play of emotion across Martin's face is its own unique pleasure. So it feels like a rare treat to see Martin's eyes widen in astonishment just before another heavy moan bursts out of him. John holds onto his smug self-possession just long enough to give Martin a light squeeze with his teeth; then he's forced to let go, turning his head to smother a chuckle in the soft swell of Martin's chest.

"Liked that, did you?" he murmurs, composing himself enough to press a slow kiss against one of the faint arcs of dimpled tooth-marks he'd left in Martin's skin. Emboldened — and not wanting to be neglectful — he gives Martin's left side a luxuriant squeeze with his right hand, rolling his nipple with artless insouciance between the knuckles of his thumb and forefinger. It almost feels cheap, just groping him like a bloody teenager, but Christ, Martin has always been a pleasure to touch. And John would like to think, by now, that he's earned a bit of indulgence.