Mizutamari Tsuyokarō is a male character who appears in the manga and original video animation adaptations of Kekkō Kamen. He serves as a punishment teacher at Sparta Academy, the corrupt and abusive boarding school where the story is set. His Japanese name can be translated as "Puddle Strong Man," and he is referred to in English materials as the Punishment Teacher. He has black hair and black eyes, and his nationality is Japanese. Mizutamari Tsuyokarō is one of the many sadistic faculty members who derive satisfaction from humiliating and torturing the female students. His role in the story is that of an antagonist who directly opposes Kekkō Kamen, the mysterious nude superheroine who protects the students. As a punishment teacher, he is responsible for disciplining students through harsh and sexually degrading methods. In one encounter, he confronts Kekkō Kamen while wielding an umbrella, but she defeats him by spinning her nunchaku to create a tornado that blows away his weapon, then delivers her signature finishing move. His motivation appears to be a twisted sense of duty and enjoyment in exerting power over the students, and he considers himself a follower of the samurai code of Bushido, as indicated by his dialogue. His personality reflects arrogance and a perverse adherence to authority, but he is ultimately no match for Kekkō Kamen's superior combat skills. He does not undergo significant character development; he appears as a recurring obstacle and is consistently defeated. His key relationship is with Kekkō Kamen, whom he tries to expose and defeat. He also works alongside other corrupt teachers and the principal, Toenail of Satan. His notable abilities include physical combat and the use of his umbrella as a weapon, but he relies more on intimidation and the institutional power of the school than on any exceptional techniques.