Yuuta takes Sora, Miu, and Hina out of their house before his relatives would come to take them. While eating lunch at a karaoke box, Kouichi attends to the three, as one of Yuuta's relatives calls, asking him to bring the girls back. Only then that he realizes the full scope of the challenge he has gotten into. Despite this, Yuuta carries on, and brings the three girls to his apartment. Meanwhile, Sora and Miu is trying their best to adjust to living in Yuuta's apartment while getting a grip on things and accept them as they are, amidst Hina's asking for her mother and father. Sora, meanwhile, is glad that she and her sisters are not going to be separated.
Segawa Yuta is a freshman of a university. He lost his parents when he was small and was raised by his sister Yuri. Yuta has been living alone since Yuri got married to a middle aged man when Yuta was a junior high student. One day, Yuri visited Yuta's apartment and asked him to take care of her three daughters while Yuri and her husband were on a trip. He unwillingly accepted the job but the plane Yuri took went missing. In order to prevent the daughters from being adopted separately by relatives, Yuta decided to take in all three girls. A life of a strange family in a tiny apartment begins.
