Kinsei no Reveal

Sugara Kugami just wants to lead a peaceful school life. But being chosen by the beautiful and talented Yui Shirasagi to be her pseudo "sister," her life is anything but peaceful. And to make things even more interesting, Yui's cold but capable identical twin sister (and also student council president), Ui Shirasagi, also takes an interest in Sugara.

(Source: MU)