Two years ago, Eri was hypnotized by Maina Ichii and her pop group ChamJam. Now the desire to see them at the Budokan burns inside of her.

A girl called "Eripiyo" is an extreme idol fan. She is wildly enthusiastic about Maina, the shy and lowest-ranking member of the minor underground idol group Cham Jam that performs in Okayama Prefecture. She gets so wrapped up in her love for Maina during a particular performance, that she has a major nosebleed. Eri will continue to give her complete devotion to Maina until the day she can perform at Budoukan (a major performing venue in Tokyo).