When Takuma, Mina, and Takuma's sister Akari go to the beach, they are expecting a day full of sun and fun. Instead, they end up helping a young boy named Rihito search for his lost robot. Rihito's robot is a "Super Mina," a more advanced version of Mina-chan. After seeing the deluxe version of herself, Mina-chan decides that, if she's to keep Takuma's heart, she needs some upgrades as well!