It is, he supposes, a fair question. Not to mention one he wasn't closely considering when he made his move on the couch. But there's no need for him to grope blindly for the answer; it is so obvious that he'd be tempted to resent Martin's inability to guess at that, too, if it wasn't so quintessentially him to not understand it at once. His confusion on this front feels like a perfect bookend to him being jealous in the first place: both symptoms of his inability to appreciate how little John appeals to the overwhelming majority of humanity.

John pulls in a breath, then puffs it out in a slow, defeated sigh. "No one's ever..." he coughs out a laugh, his faintly wistful tone hardening into something a little more sardonic. "It-it can't surprise you that no one's ever been jealous about me before." After a brief beat of consideration, he adds, "Entities aside, anyway."