He can feel his heart as it chugs harder and faster into the next beat, and Finn is forced to remember just how dangerous this was. So many clear and obvious reasons why-

And he's grinning back without thinking about it. Fear meant something when he had time to think about, to evaluate. In the moment it just made his heart beat faster. Or in this particular case, his groin grow harder. Which might have something to do with why he and Poe got along to begin with.

But beyond all that, he has his answer. In the few days Poe had been away Finn had done some...recon of his own. Beyond the very obvious aspects that came naturally, he thought he had some of more relevant basics down from study. Leaning in, Finn ran the very tip of his tongue along Poe's cock, from tip to base, then back up again on the other side.