Natural2 -DUO-

Twin sisters, Chisato and Kuu, lost their parents, and they were adopted by an old man. Then they met Shoma. Shoma was living with his grandfather because his parents were going to get divorced. Chisato was a tomboy, while Kuu was a crybaby. They both liked Shoma. 10 years have passed since then. Shoma gave up his dream to become a violinist and worked as an editor of a music magazine office. To hear the grandfather’s death, he went to the house and he had a reunion with the two girls who had become beautiful women... (Source: AnimeNfo)