Eshros is a mamodo, from his world to participate in the fight to become king of mamodo world. His partner is a large but gentle man named Shin, who was bullied throughout his childhood due to his immense size. The pair met Zatch and Kiyo, who had overheard the two were planning to destroy Shin's childhood school and has come to stop them. During the fight Shin saw Eshros for what he really was and, though they defeated Zatch, he chose to burn Eshros' book himself, sending him back to the mamodo world.