One-Punch Man Wiki

Master Joe (マスター・ジョー, Masuta Jō) was a tiger level monster who was the Treasurer of the Monster Association (怪人協会金庫番).


A human sized monster who wore a hoodie with "Joe" written on it and a mask-like face. On his face he had one eye and a mouth, they joined together to look like a key hole. He had a long black tail with three hoops at the end, resembling a key handle. He carried many keys with him, one resembling a skull that he wore as a chain around his neck, and multiple key chains attached to his waist. He also had black shorts and running shoes.


Human Monster Saga[]

Monster Association Arc[]

Master Joe is present during the raid on the Monster Association Headquarters, standing guard near the vault with a group of monsters. They are all killed by Atomic Samurai's disciples and the remnants of Narinki's Private Squad, so he rushes to open a large safe. He gets shot by Tongara, but manages to open Evil Natural Water's tank and release it to wreak havoc. He is killed by Mad Doctor Fish in the ensuing chaos.


  • His name is a pun based on the Japanese word for key: 錠 ()
  • His name also appears to be a reference to the popular lock brand, Master.
Monster Association
Executives Black Sperm *Evil Natural Water *Homeless Emperor Fuhrer Ugly Gums Overgrown RoverNyan Elder Centipede Gouketsu 
Demon Awakened Cockroach Baquma Bug God Building Booper Devil Long Hair Do-S *Eyesight G5 Hundred-Eyes Octopus Vampire (Pureblood) Rafflesidon Royal Ripper Face Ripper Fist Fight Djinn Free Hugger Rhino Wrestler The Three Crows Senior Centipede Showerhead Super Mouse Unihorn The Great Food Tub 
Unknown Gyoffrey Goddess Glasses Venus Mantrap Junior Centipede Haragiri Rosie Choze Benpatsu *Hamukichi *Volten *Evil Eye Gale Hellfire Evil Eggs ManakoPlatinum Sperm Sword Devil Executioner Raptora *Reptera
Mysterious Beings
Dragon (or higher) Boros Orochi *
Demon 170,000-Year-Old Cicada Larva 170,000-Year-Old Cicada Adult Armored GorillaAwakened Cockroach Baquma Beast King Bruinado Bug God Building Booper Deep Sea King Demonic Fan Devil Long Hair *Do-S *Eyesight Face Ripper Fist Fight Djinn Free Hugger G4 G5 Game-Berus Giant Crow Grizzly Nyah Hundred-Eyes Octopus Jumping Spider Macho Daikon Mosquito Girl Rafflesidon Rhino Wrestler Royal Ripper Scaledon Senior Centipede Showerhead Sky King Subterranean King Super Mouse Surprise-Attack Plum The Great Food Tub The Three Crows Unihorn Vampire (Pureblood) 
Wolf Himawari Hotdog Messenger of the Seafolk Piggy Bancon Tongue Stretcher
Less than Wolf
Unknown Alien Seer *Ancient King Angry Grandpa Autumn Phantom Red Golden-ringed Dragonfly *Benpatsu *Choze DarkDark Matter Gunner Eagle Enamel Evil Eggs Evil Eye Evil Natural Water *Falcon Fish of DarknessGale Giant Salamander Gigakigan Goddess Glasses Gyoffrey Hamukichi *Haragiri Hawk Hellfire Junior Centipede Kite Lord Great White ManakoMen's Esthetician Man *Platinum Sperm Rosie Raptora *RepteraSage Centipede Suppon Sword Devil Executioner Venus Mantrap Volten *