good rule of thumb

If your roommate is conducting a full-fledged investigation because she thinks that somebody may have walked off with her copy of last month's Ensign, not because she needs to use this Ensign to write a talk, or even just because she wants to read it, but simply because there's no reason for somebody to walk off with something that's not theirs, even if it is only a copy of last month's Ensign, it's probably a good idea to not ever touch any of her stuff, no matter how "communal" it may seem.

Just in case anyone may ever find themselves in this situation.