幼馴染のイジメっ子3姉妹が地元に帰ってきてから様子がおかしい。

The main character, Tanabe Yuichi, had triplet sisters who were his childhood friends.

The oldest sister, Shirota Miyako, is black-hearted and cute, the second sister, Shirota Haruka, is a tsundere, and the third sister, Shirota Minami, is quiet and reserved.

Yuichi was bullied by the triplet sisters of the Shirota family when he was in elementary school and disliked all three of them, but one day the Shirota family moved out and his life changed forever.

With the bully gone, Yuichi made more friends and became more content with his life.

Yuichi was on the road to fullness until high school, when the triplet sisters of the Shirota family returned to their hometown.

He thought he would be bullied again, but the three sisters were acting strangely. ……