...Sans keeps his trombone under covers.

[Is he investigating Sans' room or Undyne's??? He's pretty sure the trombone was Sans' item, not to mention that handwriting...

But alright, leaving that be to instead stare down at the toilet for a long, incredulous moment.]

Uh, Roxy...?

[Clearly he found something Important--]

I wouldn't eat anything Undyne or the skeletons try to make you anymore. They, uh, keep uncooked spaghetti in the toilet.

[Time to check bedside table, and the clock and TV for good measure. Gotta be thorough! Find the cloos.]