Imagawa

History
She was a bully that attended Rinne-Dō Junior High three years before the current storyline who appeared in Ira Gamagōri's flashback. During that flashback, she together with Hōjō and a large number of other students were forcing a single student to jump off the roof, under threat of firing his father from his company. When Ira, the student council president at the time, showed up to stop them from bullying the student into jumping off the school's roof, she told him that her father was the town's chief of police so even if the student did jump off he would just cover it up for her sake. The student then jumps. However, that student was saved by "The Kiryūin's Deluxe Trampoline". Satsuki Kiryūin then shows up on the upper part of the roof claiming that she had bought Hōjō's father company and that Imagawa's father was exposed of bribery and had been arrested.

Hōjō
Imagawa appears to be good friends with Hōjō.