When Izumi was really young, he was once captured during a yōkai hunt and sold to a human who was fond of collecting yōkais. He, along with other yōkais, were abused and mistreated by the owner. The owner would leave Izumi dehydrated for weeks, then he would be given some water to get him hydrated again. This would be the owner's main source of torture for Izumi as he relish in the sight of Izumi being on the brink of death and begging him for water.Ten years later, Izumi and the other yōkais were saved by the daughter of the owner, whom had stumbled upon the chamber where all the yōkais were held captive. Since Izumi was in a dire condition, the daughter had taken him to a kind doctor. After much effort, the doctor was able to heal Izumi and was able to earn Izumi's trust. Izumi became attached to the doctor and began to up to other human as well as learn that not all humans are awful beings. Through the doctor's nurture, Izumi grew to become a really kind kappa that is always helping others.Soon, a century had passed and the doctor had already passed away. Izumi had began exploring the human world, going from village to village and helping people along the way. One day, he stumbles upon a futakuchi onna named Hanabi during a yōkai hunt down and saved the onna. Despite having a bad experience with humans, Izumi decided to convince Hanabi to turn over a new leaf and not eat humans anymore. Izumi himself had grew attached to Hanabi and consider him a really good friend.Nowadays, Izumi would drag Hanabi with him whenever he wants to go have fun with the humans.