Ako, a high school freshman who wants to become more attractive after seeing how her friend Mana has blossomed through love, begins experimenting with makeup. One day, after applying a thick layer of lip tint, she accidentally collides with a boy in the hallway, leaving a bright lip print on his gym shirt. The boy turns out to be Harumi Aikawa, a senior who is famous on social media for his good looks but also notorious for hating women—he treats all girls as if they are germs and refuses to have any contact with them. He coldly tells Ako to throw the stained shirt away.

Determined to make things right, Ako has the shirt cleaned and tries to return it, but Harumi is constantly surrounded by admirers. She eventually manages to grab his hand and pull him into an empty classroom to escape the crowd. When they hear the pursuing girls badmouthing her, Harumi covers Ako’s ears to shield her—a small gesture of unexpected kindness. Later, one of Harumi’s classmates warns Ako to stay away, blaming her and other girls for Harumi’s misanthropy. Hurt but undeterred, Ako returns the next day and, in front of everyone, declares she has no ulterior motives and simply wants to be his friend.

Harumi begins to soften, which provokes the jealousy of other girls, especially a senior named Tamura who has a crush on him. Ako is called to the rooftop, doused with water, and verbally abused. She endures it with a resilient smile. When Harumi learns of the bullying, he feels responsible and starts to open up to her. Meanwhile, Ako is forced onto the relay team for the sports festival, and Tamura challenges her: whoever loses must obey the winner’s command, with Tamura demanding that Ako never speak to Harumi again. Ako trains hard but discovers Tamura is a record holder. During the race, Ako nearly loses and, in desperation, throws the baton, hitting Tamura and causing her to fall—the outcome of the bet remains ambiguous, but the incident brings Ako and Harumi closer.

As their friendship deepens, Ako realizes she is in love. She spots a photo of Harumi with a girl and becomes anxious. When she asks about it, Harumi snaps at her, but later he apologizes and invites her to his house to explain his past. He reveals a traumatic event involving a girl he failed to protect, which led to his deep mistrust of women. Ako listens without judgment and wants to help him heal. A new character, Tenma, Harumi’s classmate, begins to show interest in Ako, creating a love triangle. At a summer fireworks festival, Ako tries to reunite Harumi with the girl from the photo, but Tenma interferes. Harumi eventually agrees to talk to the girl again, but not before asking Ako for a favor in return—hinting at his growing feelings.

The story unfolds in a typical Japanese high school setting, with cliques, social media gossip, and school festivals. Key narrative arcs include the accidental meeting that breaks Harumi’s walls, Ako’s perseverance against bullying, the relay race conflict, the revelation of Harumi’s hidden pain, and the gradual shift from friendship to romance. The manga continues to explore how Ako’s cheerful determination and refusal to give up gradually chip away at Harumi’s defenses, while she also learns about self-worth and the complexities of love.