Benjamin Krupp

Personality
Benjamin is an unbelievably hot-tempered and nasty principal. He distributes detention slips to any student for even the most minor infraction, just so long as they are unfortunate enough to cross his path. In one case, he punished George and Harold by not allowing them to have cafeteria food, and makes them bring their own lunches in his office to keep an eye on them, even though he had no actual proof (however, given that the two were responsible it was justified). He once blackmailed George and Harold into doing all his daywork and even giving them extra homework in exchange for not getting "killed every day for the rest of their lives". He even tore out the last seven pages of the book, "How The Grinch Stole Christmas", to make the plot sound more realistic, assumingly cutting the book off right before the Grinch's heart grows.

His hatred towards George and Harold reaches the point where he tries to find a way to get rid of them (even if it meant that they would be killed) or (to a lesser extent) separate them somehow. In the ninth book, he was greatly happy that Tippy Tinkletrousers was going to destroy the duo, and willingly told the Turbo Toilet 2000 where George and Harold hang out in the eleventh book, so they would be gone. Also when George and Harold flunked their "Super Secret" tests, Benjamin and the faculty were greatly overjoyed that Harold flunked the fourth grade because he and George would no longer be in the same grade and thus have completely different paths.

Despite being really nasty, Benjamin does show forms of kindness. He will readily punish anyone who is bullying his nephew Kipper Krupp. Kipper just needs to yell out for his uncle and explain to him what happened, though Kipper usually makes it look like he was bullied in front of his uncle (For example: after Kipper punched a little girl in the stomach, Kipper told his uncle that the girl's stomach hit his first). Benjamin always believes his nephew's claims no matter how illogical they seem.

Benjamin also cares about his job, as he feared he would lose his job in the second book after seeing the school destroyed by the Talking Toilets until George and Harold managed to fix the school. Additionally, when Tippy Tinkletrousers unintentionally changed the past, he unintentionally caused Benjamin to be fired from his post as principal. Mr. Krupp was shown shedding a tear as he was walking away with his "Krupp Stuff." With that happening also meant that in a few more years, he himself never became hypnotized to become Captain Underpants and the villains from the first three books take over.

Depiction in the Film
Krupp is portrayed much the same way as his book self. However in the movie, he was given some sympathetic qualities where he had very little in the original books. He has a crush on Edith the Lunch Lady (who, as well, has a crush on him).

Trivia

 * Benjamin's nickname, Benny Krupp, is a pun on the word "bankrupt", and the name Mr. Krupp is an pun on "interrupt", "corrupt" and "disrupt".
 * As revealed in Captain Underpants and the Wrath of the Wicked Wedgie Woman, Benjamin is jewish, and most likely a Reform jew.
 * In the first book, he hates the Captain Underpants Comic Books that George and Harold make. Ironically, he would later become Captain Underpants himself.
 * Even though he is unaware that he is Captain Underpants, there are several times where he is doused with water in the middle of the battle with an enemy. When this happens, Benjamin is angry and confused as to what is happening, where he is, and why is he wearing his own curtains around his neck and in his underwear in public.
 * Dav revealed that Benjamin's birthday is April 1st, which is April Fools Day (same birthday as Professor Poopypants) and that he is in his mid-forties.
 * In the film, he was given a love interest, who is Edith the Lunch Lady.
 * In the film, the gold plate on the front of his desk was changed from 'Kneel Here' to 'Hope Dies Here'. Even though, some of the early film promotional pictures had 'Kneel Here' on it (or the plate was blank).
 * In the film, while George and Harold bring him home as he is knocked out on a wagon, they start to plunder in his home but found nothing interesting. On the outside, signs say "keep out", "Danger" or "Go away". No one lives in the house but him.