Hikari Shirasaka has known Yuu Takamura, her childhood friend she calls Ta-kun, for ten years. Now that they are both sixteen and in high school, Hikari suddenly realizes she has fallen in love with him. She spends her days lounging in his room, chatting about nothing in particular, and feels that they are physically close. However, no matter how obvious she tries to be, Yuu remains completely oblivious to her desperate attempts to shift their relationship from friendship to romance. Hikari is a novice at love and finds herself frustrated that the sweet, romantic atmosphere she hopes for never seems to materialize.

The story, written by Fumiaki Maruto with art by Yom, begins as a lighthearted youth romantic comedy focused on Hikaris one-sided feelings and her clumsy efforts to get Yuu to notice her. The narrative primarily takes place in and around their high school and Yuus room, where the pair share their familiar, comfortable routines.

The manga is notable for a significant structural and tonal shift that occurs several chapters into its serialization. What starts as a series of very short, fluffy, and episodic rom-com chapters, typically only a few pages long, eventually transitions into a longer-form romantic drama. This shift introduces a much more complex and emotionally charged narrative when a third character, another girl from Yuus past, enters the picture. Her appearance disrupts the simple dynamic between Hikari and Yuu, moving the story away from a straightforward childhood friend romance and into a dramatic exploration of love, timing, and complicated relationships. The ongoing story in Japan has been collected into three volumes as of early 2026.