- “Principal Vagina here. Don’t let the name fool you — I’m very much in charge.”
- —Opening line of Rick Potion No. 9
Vagina first appeared in the Pilot episode. He made a phone call to Beth, notifying her that Morty had only attended school for a total of seven hours over the course of the past two months. When it came to people mourning over the death of Frank Palicky, people were trying to take things to a racial level, saying that a Latino student did it, which Gene was trying to discourage.
He reappeared in the episode "Meeseeks and Destroy". After Summer's Meeseeks made her popular at school, he pleaded to him, asking him to help him with his divorce, before it promptly disappeared, leaving him unsatisfied and alone.
In the episode "Rick Potion No. 9", he had to interrupt Brad at the prom because he was fighting with Jessica over Morty. He took him away from her, saying that he can't hurt his throwing arm when the big game was coming up. He was later seen under the effect of Rick's love potion and fighting with Mr. Goldenfold over Morty. He presumably became a Cronenberg in the Cronenberged dimension.
Principal Vagina had his first major role in the episode, "Get Schwifty", where he denied Christianity because of how all of the giant heads were clearly seen, watching over them all. He believed that these were gods and that humans should worship them religiously and made "Headism" the true religion. He became the leader of the entire religion which many people joined including Summer and her boyfriend Ethan. However, the people started going against him when they misinterpreted the head's announcement believing they had 'disqualified' him. They saved the people he was condeming and overthrew him, tying him to a bunch of balloons and sending him away so that he may come back as a reincarnated baby. After realizing the giant heads had nothing to do with a new religion, his former followers remarked that they needed to get him down.
In the episode, "Morty's Mind Blowers", Morty confronts Principal Vagina about a new school faculty member, the guidance counselor, who he believed lived on the moon. Principal Vagina mistakes this for code that the new faculty member was a pedophile, and that he attempted to molest Morty. He later confronts him, fires him, and attacks him. The guidance counselor drove away home and took his own life. Morty was wrong about the guidance counselor, and was responsible for his suicide. He felt so guilty about it that he asked Rick to remove the memory from his mind. Although, Principal Vagina insists "that man likes them young."
Principal Vagina is a Caucasian old man with a buzz cut hairdo. He also has a bunch of tiny black strands of hair on his head. His scalp is very light, implying that his head hasn't always been shaved. He has a blue shirt and a darker blue tie.
Principal Vagina seems to be incompetent in both his personal and professional life. He seems fully aware of the coincidence in his last name, and is terribly insecure about it. In "Morty's Mind Blowers", he defends Morty from who he believed was a pedophile, meaning he is protective, and has strong moral principles.
- The character was given his surname to present to the audience with an interesting social concept that obscene words are able to be used in a socially-acceptable way when they are part of somebody's name.