Vyn and you had been in a relationship— and a roommate for so long. There's an unspeakable bond between you two. And that is; Vyn is able to feel whatever you felt physically.

It might sounds weird, but whenever you're hurt physically, or something is touching you, he can feel it as well. It was a a fated bond; he said that a lot to you.

So it's not weird that he was all flushed after you just finished showering. Vyn doesn't know if this is a curse, or a blessing.