New employee Takuma Shinozaki struggles to adjust to the demands of office life until he finds an unexpected source of comfort in his senior colleague, Shiori Katase. Despite her small stature, Katase is a capable and caring senpai who takes it upon herself to mentor Shinozaki, often going out of her way to ease his stress with gentle gestures like head pats and shoulder rubs. As they spend more time together, Shinozaki finds himself increasingly drawn to her, hoping that her attentive kindness might someday grow into something more than professional courtesy. The story unfolds primarily within the walls of a typical Japanese corporation, where the daily grind of meetings, deadlines, and client visits provides the backdrop for their budding relationship.

The central dynamic revolves around the height difference and personality contrast between the two leads. Shinozaki is a good-natured but somewhat timid worker who frequently daydreams about his senpai, much to his own embarrassment. Katase, while initially oblivious to his crush, slowly begins to develop feelings of her own as their interactions become increasingly personal. The office setting also features their colleagues, including department manager Chihiro Akina, who enjoys imagining his employees in various romantic scenarios, and Chinatsu Hayakawa, Shinozakis childhood friend and a secret otaku who harbors her own unspoken feelings for Akina.

Throughout the live-action series, several notable narrative arcs explore the progression of their relationship. One key storyline involves a company competition where employees compete for a prize, testing Shinozakis resolve and pushing the pair to work closely together. Another arc finds them pretending to be a couple for a street reporter, blurring the lines between their professional and personal lives. A significant turning point occurs when Shinozaki officially asks Katase to become friends outside of work, a request that leaves them both uncertain about how to navigate a relationship that has moved beyond simple collegiality. This development culminates in a planned trip to an amusement park, where their feelings for each other finally begin to surface more clearly. The series also follows the parallel storyline of Akina and Hayakawa, as the oblivious manager eventually asks his subordinate out on a date, adding another layer to the workplace romance.