Yuuta Segawa, a college student, is suddenly charged with taking care of his three nieces. The eldest niece, Sora, is a 14 year old in middle school with semi-long brownish hair decorated with a ribbon. The middle niece, Miu, is an elementary schoolgirl with blond pigtails. The youngest niece, Hina, is an angelic 3 year old attending daycare. This at-home romantic comedy illustrates the chaotic but heartwarming lives of these four characters in their tiny one-room apartment.