Koji Maeda is the central male protagonist. He lands a waiter job at Pia Carrot restaurant despite arriving late to his interview. This follows an initial encounter with Azusa Hinomori involving a physical collision that led to a compromising situation, establishing immediate mutual hostility. His persistence directly secured him the position.

Characterized by a notoriously perverse streak, this trait fuels recurring conflict, especially with Azusa, who strongly disapproves. Early tensions escalate when he discovers and openly mocks a handwritten note inside her cherished pendant—a sentimental inheritance from her deceased parents—expressing her desire for a boyfriend. This act demonstrates his initial insensitivity to her personal history and emotional vulnerabilities.

His romantic path is complex, involving multiple relationships within the restaurant staff. He develops a significant connection with Tsukasa Enomoto after rescuing her from drowning, leading her to see him as a hero. They date following a temporary separation from Azusa, but this relationship ends when both recognize Koji's unresolved feelings for Azusa, prompting an amicable mutual breakup.

A notable subplot involves Jun Kagurazaka, an aspiring actor working at Pia Carrot disguised as a male to prepare for a role. Unaware of Jun's true gender, Koji experiences confusion due to an unexpected attraction, questioning his sexuality. This resolves when Jun's identity is revealed, leading to a brief romantic involvement that transitions into platonic friendship after Jun departs to pursue acting.

His romantic focus ultimately centers on Azusa. A pivotal moment occurs when her hopeful expression during a misunderstanding—where she mistakenly believed he was inviting her on a date—crystallizes his realization of his feelings. This leads to a genuine romantic overture and their subsequent relationship. However, their initial relationship faces a significant challenge when Azusa witnesses Rumi Kinoshita kissing Koji on the cheek, misinterprets it as infidelity, and causes a temporary breakup.

Following this separation, Azusa briefly dates Shinji Yano (Koji's friend and Ryoko Futaba's cousin). Meanwhile, Koji pursues relationships with others, including Ryoko Futaba, where mutual attraction culminates in a brief physical encounter after he rescues her from an assault, though it doesn't develop into lasting romance. He also shares a purely platonic, brotherly bond with Mina Hinomori, Azusa's younger sister, who actively supports his eventual reconciliation with Azusa.

The narrative resolves with Koji and Azusa mutually confessing their enduring feelings, re-establishing their committed relationship. This reconciliation is facilitated by the understanding and encouragement of their former partners, Tsukasa and Shinji, who recognize the depth of Koji and Azusa's connection. Their status as a couple is maintained in subsequent appearances within the series' continuity.