The plot of this amusing romantic comedy revolves around a young 19‑year‑old college student named Segawa Yuta. Having successfully entered college, he begins a carefree life with new friends, but the sudden disappearance of the plane on which his older sister and her husband were traveling abruptly changes the boy"s plans. Now Segawa will have to take care of his three nieces: Sore (a high‑school student), Miu, a fifth‑grader, and Hine, a preschooler. All of them will have to live together in Segawa"s small apartment (3 by 4 meters).