Forbidden Love (2008)

Fashion designer Mizuki Ritsu returns from abroad and ends up sharing an apartment with his boss's son, Sho, and his younger brother Ryo. Sho refuses to go out of his room and doesn't want to see anyone. Because of this, his father wants Ritsu to watch over Sho and take care of him. Unknown to everyone, Sho and Ritsu used to be lovers before Ritsu left Japan and went to study in New York.