In beach volleyball, there is no room for aces. To achieve victory, each player must find their one, irreplaceable partner that they can rely on in the court of sand. At least, that is what Haruka Oozora learns on her first day in Okinawa after moving in with her grandmother and her cousin Kanata Higa. While touring a nearby beach, Haruka stumbles upon some girls practicing beach volleyball and is quickly invited to join. This friendly practice game suddenly turns into a match when one of the girls, Narumi Tooi, notices Kanata approaching the court.