Friends but Rivals.Haruka comes to Nijigasaki with Himeno Ayanokōji from Tooh Academy to invite the School Idol Club to Diver Fes, an annual music festival held in Odaiba, that they will also be attending. However, Nijigasaki can only perform one song, and they realize only one girl with have a chance to perform. Karin continues with her modeling work, and runs into Setsuna, Ayumu and Yu while trying to find a dance school to improve on her dance skills. After talking with her, Setsuna suggests they all discuss who will perform at Diver Fes again, with the others choosing Karin...