Oraku is a high wizard with the power to control water. He has a little problem, though. He and his apprentice, Kariya, have to find a goddess that will help them save the world from an evil lord of darkness. However, this goddess' soul is trapped in the body of a demoness by the name of Isuri, and Isuri casts a spell on Oraku that not only makes him younger, but makes him one of the most perverted freaks on the planet. What's a poor guy to do?

Oraku is the main character of Erashiya: Kijo no Immature, a story about following your dreams, no matter how impossible they may seem.