Rin, Shiemi, and their classmates are assign by Yukio to find the misfit ghost who haunts the amusement park. Rin and Shiemi are pair up, and the two agree to enjoy the amusement park another day together (like a date). While Shiemi plays with the young ghost boy, Rin fights Amaimon who takes Rin's sword. During their fight, a beam almost kills Shiemi which Rin blasts it with all of his might. Shura, who was in disguise as a hooded boy, appears to save Rin's life from Amaimon. She reveals that she is an inspector which shocks Yukio, Shiemi, and Rin.
Mephisto gazes upon Amaimon's collection of Japanese souveniers. Although Amaimon uses the key of infinity, Mephisto jumps for joy when he sees the Honey Honey Sister Yukata. Mephisto embraces the samurai spirit and moe, and when Amaimon asks Mephisto where Rin is, he points to an amusement park. Amaimon bites his nails with joy.
In Mepphy land, the male students wait in front of the entrance. Ryuji and Bon ask about Rin and Shima's last mission that involved a giant squid. Ryuji expresses his anger for the two male classmates (the hooded one and the one who has a hand puppet) since they do not do anything. Shiemi and Kamiki rush to the entrance of the park. Everyone gaze upon Shiemi's new look because Shiemi wears a school uniform. She apologizes to her classmates since she did not know how to put on, and she tells Rin that kimonos would get in the way of battle. Rin asks Yukio if Shiemi's skirt is too short. Yukio evades the question which Rin asks Yukio if he was staring at Shiemi's breasts. Yukio smacks Rin with his book. Yukio prepares to pair everyone: hooded boy and Ryuji, Bon and the boy who has a hand puppet, Shima and Kamiki, and Rin and Shiemi. Rin blushes once he hears Sheimi is with him.
Yukio briefs them about the mission. He explains that they shut the park for one day to find a young ghost boy who been naughty. Yukio tells his students to call him or Mr. Tsubaki once they find the ghost. Mr. Tsubaki asks the students what is the definition of a ghost. Kamiki replies that a ghost is a demon who possesses corpse. After Yukio explains that there is one ghost, everyone search for the ghost.
Ghost boy gropes Shiemi
Rin stares at Shiemi's body, and he thinks that they are on a date. When Shiemi walks strangely, Rin asks her if something's wrong. She reveals a pouty face. Without reason, she continues to walk away until she bursts into a smile upon looking at the roller coaster. She explains that she cannot stand crowds which is why she never visit an amusement park. Rin proposes that they should "hang out" together. Shiemi agrees while Rin gets all jolly. Rin and Shiemi has established a "date." While the other exorcists search for the ghost, Rin hears a voice from the merry go round. Rin and Shiemi find a crying ghost boy. At first, Shiemi goes to comfort the boy, but Rin tells the boy to stop crying. The boy hugs Shiemi and tells that his mother and father did not let him play in the amusement park due to his sickness. He tells Shiemi that he is lonely which prompt Shiemi to pet him. The boy touches Shiemi's breasts, and Rin gets angry (even though he wants to do same thing). Shiemi chases after Rin. Shiemi tells Rin that she will look for him.
After she seen the boy runs off to a mirror house, she goes after him. Shiemi suffers a head injury after bumping into a mirror. Before Rin can call Yukio, Amaimon steals Yukio's sword. Amaimon introduces him as an older brother of Rin. He tells Rin that he will not give the sword back. As Amaimon unsheathes the sword, Rin's blue flames appear.
Amaimon teases him
Ryuji yells at the hooded boy to search for the ghost. Suddenly, the hooded boy climbs up the building. Meanwhile, Shiemi rides with the ghost boy in those teacup rides. Back to Rin, Amaimon repeatedly unsheathes and sheathes the sword. Amaimon notes that the blade is an entrance to Gehenna while the scabbard is the doorway of Gehenna. Therefore, sheathing the blade is like closing the entrance. Finally, Amaimon completely unsheathe the sword. Rin charges at Amaimon while Amaimon tells him that he will play with him. As the amusement park turns on, Yukio and the others are aware. Amaimon taunts Rin by getting him to play tag with him. Meanwhile, Shiemi wakes up. The ghost boy calls Shiemi a demon and tells her to chase him. Shiemi realizes the boy is like her and agrees to chase him. Rin is climbing up the roller coaster tracks until Amaimon rides on the roller coaster that is coming towards Rin. As Rin jumps out of the way, Amaimon flicks Rin's face which sends him plummeting to the ground (another game Amaimon learn in Japan).
Rin gets stepped on
The hooded boy leaps off while Yukio watches the destruction of the roller coaster. Amaimon grabs Rin in mid air and continues to punch him. Amaimon knees Rin into the ground, and he tells Rin that he is disappointed. At a balloon house, Shiemi finds the boy. Back to Rin's fight, Rin knocks back Amaimon and pins him. Amaimon gets happy that Rin is powering up, so Amaimon smashes the ground with his fist. This causes the beams to fall into the balloon house where Shiemi is at. Shiemi, who holding the ghost boy, watches the beam slowly fall on her. She tries to walk away, but it is too late. As she screams, her greenman spirit sprouts roots. Rin, who sees Shiemi in danger, blasts the beam with blue flames. Shiemi, who does not know what happen, watches the boy fly around with enthusiasm. He thanks Shiemi for giving him a fun time, and he bids her farewell.
In Rin's battle, Amaimon steps on Rin. The hooded boy (Shura in disguise) chants an incantation, "Devour the Eight Princesses" and takes out a sword from her chest. Shura attacks Amaimon, and she asks him if Mephisto brought him here. Amaimon throws the sword to Rin, and he runs away. Shura tells Rin to hide his tail. Rin thinks he is no different from before since he cannot defeat Amaimon. Shiemi runs to Rin and asks him about his well being. Rin smacks her hand away, but he apologizes to her when he sees her face. Yukio arrives, and Shura tells Yukio that he is late. As she takes off her disguise and sarashi, the others get surprised. Shura explains that she was sent heare to investigate with an order from the Vatican Headquarters of the Knights of the True Cross. In addition to an upper level exorcist, Shura is also senior exorcist first class.
- Japanese Name: "Onigokko" (鬼事)
- Manga Chapter: Chapter 9 (Volume 3)
- Opening Theme: "Core Pride" by Uverworld
- Ending Theme: "Take Off" by 2PM