Hey, what's a few harmless japes between roomies? Passes the time, don't it?

[But it's paired with a chuckle.]

Well, just so it's out there - you ever need a couch to crash on, you're free to stop on by. Can't guarantee the place won't be smokin' like a crater half the time.

[In a stage confidential undertone, he adds:] Undyne likes to try her hand at cookin'. Emphasis on "try."