Well, to be fair to Denji, this is kinda what they get up to: hooking up with strangers. There aren't a lot of out gay people in Japan, so hooking up on the DL is commonplace.

He lets out a pleased hum as Denji starts to grind down on his tongue, letting out a moan before going back at it. Fuck he's loving this. Having a cute boy, letting him play with his body. It's the fucking best. It'd be better if they were both naked because he'd love to suck on Denji's nipples, but, hey, some people are weird about stuff, so he's not too fussed about it.

He keeps going, alternating between lapping at, swirling around, and poking at Denji's hole with his tongue, eyes half-lipped, watching the other face.