My first thought was more along the lines of "I can't believe we just did that in the shower". ( there's slight tilt to the corner of his lips; billy's smiling despite himself, leaning into loki's touch. it feels good, like this. ) Followed by "I'm glad Loki's not tripping over his own feet, dying in his shower after all this'd be an embarrassing way to have my corpse found" and "A bath would be easier, next time."

( among several other things, but loki doesn't really need to know everything that went through his head. ) I think that was the sixth? Seventh place my mind went.