Formal name for the rim of the toilet bowl. Should never be sat on for reasons the known as the four p's: Piss, Poop, Puke, Period.
Stumbling home after a night of drinking, Rookie sat down to take a shit, but forgot to put down the lid on the thrown and sat on the Forbidden Seat. Next morning he woke up with syphilis. Jovanny laughed his ass off.