メイプルカラーズHHH クラス全員俺の嫁！

Shinji transferred into the special class at Kouka Academy, where he was the only male student. He was forced to do so by his mother, the school’s board chairwoman, who wanted him to find a bride so she can have a grandchild as soon as possible. All 14 of the girls in his class were gathered there as his potential brides, and he was given a permit which allowed him to have sex with any of them. While he was met with cold stares at first, they soon warmed up to him as they worked together preparing for the school festival. And so begins his harem-like school life with his classmates full of individuality.

[From Hau~ Omochikaeri!]