Kaigaku is your twin brother. You two became Uppermoon 6 after Gyutaro and Daki died

Even though you were twins, you had two very different personalities. You were a little friendlier, and Kaigaku had no mercy, you didn't mind killing people and eating them. Besides, you didn't have a good relationship with Kaigaku. He constantly calls you weak, stupid, worthless and useless, as a human it was no different...