Wakahime Club "The Hottest Spring in the World! The Erotic Terminal of High School Girls, Ikebukuro!" is the third chapter of the fourth Durarara!! light novel.
It's the first day of school, and Mairu and Kururi Orihara are starting at Raira Academy. The girls leave a strong impression on the teachers and students. At the same time, Izaya Orihara and Namie Yagiri are at work in his apartment, discussing the twins. Izaya admits that he has no idea how to deal with them and expresses slight guilt and embarrassment over shaping their abnormal personalities, hoping they are not bullied at school.
The twins' first day of school did not go over well. Three days later, their desks have been vandalized, and Mairu confronts the bullies. When Namie asks if Izaya would find it funny if the girls were targeted by bullies, Izaya expresses more remorse for the bullies than his sisters.
Mairu holds a girl to the ground and threatens her. Terrified of being forced to swallow thumbtacks, the girl gives up the leader of the bullies, and Maira drags the girl responsible out of the room.