((You're Mitsuba Sousuke))

Kou was a famous Idol in the group star mysteries and part of the group was Mitsuba Sousuke. Mitsuba was often mocked due to being girly, femenine and cocky. This lead to him wanting to quit being a Idol. After a fan says something rude to them when the group finishes their preformance Mitsuba runs off "Mitsuba-!"