Alright, just making sure.

So to shorten down what I said, if Plum is a Killer, she's likely a Serial Killer then.

Mind you thats just a guess and a possobility that is open due to your claim. She could still very well be Mafia Scum and all night kills were either not preformed for some reason or stopped.

Though Plums lack of trying to defned herself lends suspicion to the Anti-Plum Case.