S1·E5 Now it's War? The Dangerous Principal Edajima's Dutiless Battle

Togashi, Tazawa, Matsuo and Hidemaro decide to test Principal Edajima's skills, but mistakenly attack Oni-Hige instead. For punishment Togashi must do the Boulder Bunny Hop. Oni-Hige takes Tazawa, Matsuo and Hidemaro to Rakkyo University where he accuses the students of pursuing pleasure and fashion. He then suggests that they buy and wear traditional loincloths with Otokojuku logos. When they laugh at him, he orders his students to beat them into submission. They are stopped by the manly Rakkyo University Cheer Squad and held hostage for a 1 million Yen ransom. Principal Edajima decides to rescue them himself. He arrives in a tank and destroys the clubhouse, and when confronted by the police, claims that he's making a movie. He beats up the Rakkyo group, earning the respect and admiration of the Otokojuku students. In the final scene he rides off into the sunset on his tank.