Sanguijuela's story

Name: Sanguijuela
Age: 17
Gender: ???

As a child, Sanguijuela was named "Ri". After Ri was born, his village was attacked by a demon king. The demon king attacked alone, but he had control of a rare species of slug called "Arion". These Arion helped the demon king in return for the flesh of the demon king's victims. These Arion respond to the demon king's chakra.

Ri was offered to this demon king as a child in order to save the village. Instead of killing Ri, the demon king took him under his wing. The demon king inplanted his left eye on the Ri's back. The demon king's eyes emitted chakra, which allowed Ri to control the Arion. After learning control the chakra emitting from his back and learning to mix that chakra with his own, Ri became a killer. If annoyed, he usually tried to fatally injure opponents or outright kill them. Eventually, a powerful opposition came up against the demon king and killed him. Ri took the demon king's remaining eye and implanted it into the back of his right hand, giving him complete control over the Arion. However, Ri was knocked out and he woke up with his memory and without the ability to completely control the demon king's chakra. Therefore, his battle prowess lowered.

When he woke up, the villagers named Ri "Sanguijuela". Sanguijuela is a calm person, but in the heat of battle, he reverts back to his killer self.