"More Than a Married Couple, But Not Lovers" centers on a unique premise involving a high school program designed to prepare students for adult life through simulated marital experiences. The story revolves around Jirō Yakuin, a reserved and somewhat socially awkward student, and Akari Watanabe, a confident and popular girl. Despite their contrasting personalities, the two are paired together for the program, which requires them to live together and perform tasks as if they were a married couple. Their performance is evaluated based on compatibility, communication, and cooperation, with the top-performing pairs receiving special benefits.

Initially, Jirō and Akari struggle to find common ground, as their personalities and priorities clash. Jirō harbors feelings for his childhood friend, Shiori Sakurazaka, who is paired with another classmate, while Akari is determined to win over her crush, Minami Tenjin, who is also participating in the program. As the story progresses, the forced proximity and shared experiences begin to foster a deeper understanding between Jirō and Akari. They gradually develop a bond that transcends their initial reluctance, navigating the complexities of their simulated marriage while grappling with their genuine emotions.

The narrative explores themes of personal growth, emotional vulnerability, and the blurred lines between pretense and reality. Secondary characters, such as Shiori and Minami, add layers to the story, creating a dynamic interplay of relationships and unspoken feelings. The program’s structure serves as a catalyst for self-discovery, as Jirō and Akari confront their insecurities and learn to communicate more openly. The series balances lighthearted moments with introspective scenes, capturing the awkwardness and sincerity of adolescence.

As the story unfolds, the central tension revolves around whether Jirō and Akari’s evolving relationship will remain confined to the boundaries of the program or develop into something more genuine. The manga delves into the nuances of human connection, examining how shared experiences can reshape perceptions and foster unexpected intimacy. Through its exploration of love, friendship, and self-awareness, "More Than a Married Couple, But Not Lovers" presents a thoughtful and engaging narrative that resonates with themes of personal and relational growth.