Ane Jiyoku Tsukushi Neesan no Shitagi - 1

Amy, the president of the student council, is a beautiful, ideal and quiet girl. Her younger sister, Ryuka, is comparable to the idol in popularity and is always in the spotlight. The younger brother of these two beautiful girls is Mizuki, the most ordinary boy.
Since childhood, Mizuki, a quiet and perfect Amy constantly lifted up and was too demanding on him. However, the life of Mizuki changes when he has a girlfriend.
The spring of love at Mizuka is destroyed by the fact that he accidentally finds his girlfriend cheating on him with another. On the same day, Amy comes to console his brother and recognizes him in his feelings, the result of all this is stormy sex.