Haruki works part-time at the Shibuya store of the apparel brand Berry, which was launched by her childhood friend and the brand's president, Tadato. She is the top salesperson and has the most SNS followers among the staff, and she dreams of one day running her own brand while nursing a crush on Tadato. When a sales competition is announced, with the prize being the right to produce a brand, Haruki eagerly jumps at the chance to get closer to Tadato and her ambition. But her rival turns out to be Kairi, a popular social media influencer and a younger high school student who has just started working at the same store. Kairi boldly declares that if he wins the sales battle, Haruki has to fall for him. What begins as a professional rivalry soon becomes a tangled love triangle, with Haruki caught between her long-standing admiration for the mature Tadato and the pushy, increasingly sincere advances of the brash but charming Kairi.

The story follows Haruki's emotional and professional growth through several major narrative arcs. After accidentally witnessing Tadato kissing another woman, Haruki loses her passion for fashion entirely. Kairi, initially just a rival, gradually pulls her out of her slump by taking her on dates and spending more time with her, and Haruki begins to see him in a new light. She ultimately wins the sales battle and secures the brand production rights, but her feelings remain unresolved. To create distance from Tadato, she agrees to a fake relationship with Kairi, which only intensifies his genuine affection. Kairi openly declares himself as Haruki's boyfriend in front of Tadato, forcing the older childhood friend to confront his own long-suppressed feelings. During a pop-up shop event in Sapporo, tensions escalate: Kairi challenges Haruki to another sales battle with a kiss as the prize, while a drunken Tadato kisses her, further complicating the situation. Haruki's heart swings between the two, but after Kairi's honest confession and Tadato's sudden declaration of love, she realizes her true feelings and chooses Kairi. The final volume shows the newly formed couple deepening their bond during a trip for brand inspiration, navigating jealousy and miscommunication, and ultimately solidifying both their romantic relationship and their future in the fashion industry.