Dr. Donut

Dr. Donut is a Candy Person who appears in "Mystery Train" as one of the apparent murder victims aboard the train. Dr. Donut is the fourth Candy Person whom Finn accuses and was murdered immediately after said accusation. He is the second doctor, after Nurse Poundcake, in Ooo without a Scientific Parasite in his front pocket; presumably due to the fact that he has no pockets.

Quotes
The only four things Dr. Donut has said are "He doesn't look good.", "I think it was the guy who screamed "I'm gonna kill you".", "You...think it was me?" and "Are you kidding?".