S.O.S.! The Wrath of Happosai (SOS エロ妖怪八宝斉 SOS Ero Yōkai Happōsai?) is the 17th true episode in the second season of Ranma ½, Anything-Goes Martial Arts, though it is treated as the 20th episode, and is the 38th episode overall. When Happosai's shameless depredations endanger the reputation of the Tendo Dojo, Ranma is called upon to try and reign him back. However, the selfish little monster takes this as a personal affront, beginning a vendetta against his "insolent heir".