Regardless of whether the individual moves out on good or bad terms, you will never be able to get in contact with this individual ever again.
Roommate 2: Uh, no, she pulled a Maggie Moveout, so we will literally never hear from her again...
Roommate 2: And dude, it's weird anyways, because you and I have moved into a new apartment, and her mail from the old apartment we shared with Maggie *followed us here.*
Girl 1: This isn't Diggens! What happened to the underbite dog?
Guy 1: IDK, I got blindsided by a Maggie-moveout, and I haven't seen Diggens since. I hope he's O.K. This is my new roommates dog, Roxy.
Girl 1: Oh, what a cute Boxer! Come inside and grab a drink.