Shindou-ke no Jijou: Gravitation N.G.

Riku has grown up without many friends, because everyone called him a liar after he said that his "mother" is actually a man. Now in high school, he has come to terms with his decision that it's simpler socially if this fact is kept secret.

However, his mother (Shuichi Shindo from Gravitation) is supposed to come with him to school tomorrow for a parent-teacher conference!

(Source: MangaUdates)