Does the light bulb always disappear around the same time?

I wonder if there's an adhesive that takes a while to set, but once it's bonded, it's hard to get off. If so, I'd put a little bit of that on the bulb (brush it on when it's screwed in) and wait for that little fucker.

When you know who it is, you take his ass to the building manager/super with solid evidence and try and get them evicted.

Serves the little bastard right.