@ottumon I had a lot of storage space under my bed as a kid. I used to store all sortsa shit under there, so... if a monster was actually under my bed, first it would have to be real quite so as not to disturb anything under there, AND compete wiht the cat who would likely be under there sleeping.
If they managed that, as long as they didn't wake me up playing with my legos, they could stay, fuck it. Just you know, clean up after, don't lose any bits, y'know?