Kinsei No Reveal

Kugami Sugara just wants to lead a peaceful school life
But being chosen by the beautiful and talented Shirasagi Yui to be her pseudo sister her life is anything but peaceful
And to make things even more interesting Yuis cold but capable identical twin sister and also student council president Shirasagi Ui also takes an interest in Sugara
From there things go as well as you might expect in this yuri comedy