Aina Shinkawa's wife began working at the same school, assigned to a co-ed class that had already collapsed due to delinquent students. Initially worried, Aina enthusiastically embraces the challenge, declaring, "This class has real potential!" However, the class is filled with vicious, unruly thugs, putting her at risk of getting caught up in serious trouble. To protect Aina, he may have no choice but to insert himself directly into that dangerous classroom environment.