Oteuchi Kakugo!

Oteuchi Kakugo! summary:

Kyouta Sakurai is a student in the second grade of a prestigious high school. He is suddenly assigned to be a chairman of the students council, instead of Kei Mikami, a very beautiful, respected and intelligent vice-chairman. The members of the council are cold to Kyouta because of that and Kei says to him "You are just a symbol. I will do everything instead of you". But Kyouta still tries to be as good a chairman as he can. When he is nearly raped, Kei saves him and orders Kyouta to be his pet in return of his support with the council work...