Gyoza makes his debut in episode 10, immediately establishing himself as money-obsessed—a trait that seems shallow until his real motivation gets revealed much later. His sister is seriously ill, and the only medicine that can help her is monopolized by Truffle, one of Death Metal's Four Heavenly Kings, making treatment ruinously expensive. What Gyoza doesn't realize is that Death Metal created the problem in the first place; his sister would never have needed ongoing medication if they'd just moved away from the town.
Once Gyoza figures out the truth and confronts Death Metal, he leaves his sister with Sanratan and throws in with Team Freedom. He travels with them for a solid stretch until episode 37, when he and the Triceradogos take a beating severe enough to sideline him. That's when he heads off with Sanratan again to recover.
Content compiled by AnimeList.moe from publicly available sources.
