S1·E3 How's the Water? This is Otokojuku's Oil Bath

The Otokojuku instructors put the students on a strict, and very unpopular diet so two students decide to raid the kitchen. The Instructors are also concerned about the students forming a union. Momotaro takes the blame for the kitchen raid and is put in the Prison of Penitence. Just as Momotaro's punishment is finished, the Pure Evil Group attacks the school. Togashi Gengi volunteers to take Momotaro's place in the Oil Bath of Hell to appease them and suffers a great deal. He does this in return for Momotaro's help earlier. As Hidemaro and the Pure Evil Group leave they are met by uncle Bro Yasha the Assassin assigned to take revenge. Momotaro beats him, and Yasha suggests that Hidemaro join the Otokojuku to develop his manhood.