A powerful old man possessed of an evil spirit. He is the feared and loathed sensei of Genma and Soun. 10-several years ago, he harshly trained them by making them take part in his plundering and endure the punishments when he left them behind. Finally, they got him drunk, chained him in a barrel, threw the barrel in a cave, and sealed the cave with dynamite and a boulder hung with Buddhist scriptures. Years later, he escapes. He moves into the Tendo Dojo to train his successor, where Genma gives him Ranma to train. A 110% pervert, he constantly goes around lifting skirts, stealing women's underwear for his extensive collection, and committing frontage. His perversions are the source of his strength; without touching young female bodies or underwear, he loses his power. Ranma-Chan and Akane are his favorite targets. Personality: Extremely obsessed with girls' bodies and underwear, he is also rather unforgiving and a bit evil. He particularly targets onna-Ranma and Akane, and will use magic, force, underhanded tricks and just about anything else to get what he wants. Happosai considers himself to be Ranma's master, and expects him to behave accordingly, but Ranma never has - most likely because Happosai likes splashing Ranma with water, and enjoying the results.
