Other than the full-body shiver that G'raha gives at the attention to his tail, it doesn't seem as though his physiology is all that different from what Vanitas seems to have experience with. While the Miqo'te has studied up on intimacy given his stretches of downtime over the years, he's never been of the mind to put it into practice with just anyone.

Clearly, this place has a way of changing one's mind.

He yowls when that bundle of nerves within him is all but attacked, rocketing swiftly toward even higher heights of pleasure. "Gods, yes--"