Maiku Kamishiro

Maiku Kamishiro's past has always been somewhat of a mystery to him. The only clue he has to who is family might be is an old photograph showing two young children, a boy and a girl, playing in a small pool outside of a blue house. In an attempt to find his family, he moves to this blue house and begins working as a programmer. He's living a comfortable life until the day two very different girls show up at his door, both in possession of the same photograph, and both claiming to be his twin. With no way to prove who is a relative and who is a stranger, Maiku allows both girls to move in with him until they know for sure. (Source: Anime News Network)
After Kamishiro Maiku recognizes a house on television that appears in a photo that was left to him by his parents, he decides to go live there. Then two girls show up on his door step to move in, claiming to his twins.
Maiku has the same unusual blue eyes and the same childhood photograph as the girl at his door. They might be related.
Maiku has strong feelings about not abandoning a relative, so Miina can stay until they know otherwise.
Miina drags Karen along to a job interview so they can help with bills.
Karen and Miina begin attending Maiku's school and discover rumors that Maiku doesn't like girls circulate.
Maiku worries as the girls attempt to avoid him so they don't have to discuss their changing feelings.
After winning the grand prize in a lottery, Maiku, Miina and Karen head to the beach.
Maiku learns the truth of Shimazaki's sexuality. Shimazaki reunites with Tsubaki, whom he was previously in love with.
On a beautiful day, the three head to the mall, but end up getting lost from each other.
Maiku and Karen learn of Miina's past. Karen then find out that the picture of Maiku and one of the girls was taken at a different angle.
Karen goes on a date with Maiku before telling the others that they're siblings.
Miina runs away, twice. But Maiku won't let her go so easily.