Maiku Kamishiro has always had a photo of himself as a child in front of an old house with a young girl. One day after spotting the building in a news report, the high school boy moves to the countryside to live in the house from the picture. While living alone, making ends meet by working as a freelance programmer, Maiku gets the shock of his life when not one, but two girls turn up on his doorstep claiming to be his twin sister! With the lively Miina and timid Karen both possessing the same photograph, the pair begins living with the confused Maiku as they try to figure out which one of them is actually his sister.