Toshishita no Ryuugi

年下の流儀

Yuusuke and Atsushi are not connected by blood. They have not seen each other for several years. Atsusi matured, and even became much more than his older brother. He moved to enroll into University. Yuusuke receives an unexpected visit from Atsushi who has come to live with Yuusuke. (Source: M-U)