Upon returning home from school one day, Masamune Makabe is joyfully greeted by a young girl who he mistakes for his ever-cheerful mother. However, he quickly learns that she is actually his cousin Haruka. In fact, Haruka, his mother, and his Aunt Asae all happen to look strikingly similar to each other. Seizing the chance to reap the benefits of the situation, Masamune's sister Chinatsu persuades the three to dress up and have some fun.