Normal Person
It’s crucial to vet potential roommates because nobody wants to live with a lunatic. But sometimes people have a normal appearance that hides a psychotic mindset. One internet user said that they accepted a housing application from a relaxed and well-dressed man. But he went crazy on the first day and didn’t last long.

“His first day he showed up with a case of Milwaukee’s Best Ice and trashed the kitchen,” the Redditor described. “He left beer cans all over the place, cigarette burns on the couch (it was a non-smoking house), the microwave had macaroni and cheese in it.”