Kageri ni Komorebi, Sore kara Midori

Taishou Era Year 2. Having become the head of a noble house at a young age, Kuroki is reacquainted with his school friend, Arima, at a dinner party. Though rumors are flying about Arima, Kuroki is nonetheless drawn to the whimsical, no-account Arima. However, since he must live his life for his noble house, he understands to a painful extent that he is not free to fall in love where he likes. While attempting to stifle his ever more violent feelings, he deflects his awakening love. Even so, Kuroki doesn't want to sever his ties to Arima... (Source: Fujoshi Bitches)