Saihate no Kimi eHaruka Minami2004

Following their parents' deaths, Masaya and his younger brother Ryou are brought to the Takatou Estate. They are forced to live in the servants' quarters, where Ryou spends his childhood as the companion and lover of the Takatou family heir, Akahito. He stumbles upon a secret which changes his life forever. While Masaya's life is now at stake, Ryou's status changes from that of Akihito's lover to his slave. Friendship and companionship give way to brutality and violence. It's up to Ryou to rescue both his brother and himself from the family he once trusted.