Sakuta had been unable to see Mai, who was not only busy with work but had an order from her agency forbidding her from going on dates. The second term finally begins, and Sakuta is eagerly looking forward to seeing Mai again at school. But upon seeing Mai in front of his house, she greets him with a shocking, "Who the heck are you?" Upon confirming what the circumstances are, it comes into light that Mai and her little sister Nodoka Toyohama have swapped bodies. Until this new Adolescence Syndrome is resolved, Mai will be living as Nodoka, and Nodoka will be living as Mai...

Unable to deal with a commercial filming well as the actress Mai Sakurajima, Nodoka gradually starts to feel a strong sense of inferiority. As their body-swapped lives continues on, the day arrives where Mai must perform in Nodoka's pop idol group "Sweet Bullet". Sakuta and Nodoka attend the concert as they were given tickets...