A trivial matter leads to an argument between Negi and Asuna. The two struggle to find an opportunity to make up. Wanting to cheer up the dejected Negi, the Class President invites him to a private island via private jet. However, for some reason, all 31 classmates end up joining them. Contrary to the island's liberating atmosphere and lively, cheerful mood, the relationship between Asuna and Negi shows no sign of improvement. Their concerned classmates try various schemes to help them reconcile, but not only do they fail, they end up making Asuna angry instead. In his panic, Negi accidentally drops his precious glasses into the ocean. Those glasses were a cherished memento given to him by his older sister, Nekane. Upon hearing this, Asuna heads out alone into the midnight sea to search for the glasses...