The Esquires are tasked to look for the ghost of a child that is haunting Mephisto Pheles' amusement park. Rin and Shiemi manage to find the ghost first, but Shiemi ends up chasing it by herself while Amaimon, a higher demon and another son of Satan, steals Rin's sword and forces Rin to fight with him. Meanwhile another exorcist comes to defend him, and she is revealed to be an old friend of Rin's father.