Changing schools is something Yuuichi is accustomed to, due to his parent's profession, and with their recent venture to Africa, he is returning to his aunt's home after 7 years. The time that has passed since his last visit has faded his memories of the people he knew, and the ties that bonded them to him, including his cousin Nayuki. Slowly those people, coincidentally all being girls, find their way back to him. (myanimelist.net)