Is this thrilling feeling friendship? Or something else…? The innocent and cheerful transfer student, Shun (春), makes the heart of the prince of the girls' school, Natsuki (夏月), race uncontrollably. Natsuki feels both flustered and delighted by Shun's different attitude compared to other students, constantly thinking about Shun. And when Natsuki sees Shun getting along with other students, feelings of irritation and anxiety arise…. Natsuki begins to realize that they can no longer suppress their feelings…!?