Located in an unspecified part of Japan, Rinne-Dō Junior High is the school where Ira Gamagōri attended during his time as school president. There were some problems with the local bullies Hōjō and Imagawa.
When an unnamed student one day accidentally spilled milk on Imagawa as seen in a flashback, she and Hōjō along with their gang took the boy to the roof of the school and ordered him to jump off it to prevent his father from being fired.. Ira showed up in an attempt to prevent the boy's forced suicide. Imagawa claimed to Ira that she wouldn't be arrested for this orchestration since her father is the town's police chief. Despite Ira's attempts, the student jumps anyway. However, the student is saved "The Kiryūin's Deluxe Trampoline". Satsuki Kiryūin then shows up with her butler Mitsuzō Soroi on the upper part of the roof complimenting her trampoline move. After being threatened by the bullies and Ira grabbing the student, Satsuki revealed that she had already removed the bullies' parents from their positions of power by buying out the company owned by Hōjō's dad and exposing Imagawa's dad for taking bribes that led to his arrest. After single-handedly defeating the bullies and their gang with her katana, Satsuki announced her rule over the entire junior high school body.