"Kekkon Shiyō yo" centers on the lives of two individuals, Shōta Takanashi and Rui Tachibana, who enter into a marriage of convenience. Shōta, a reserved and hardworking salaryman, is pressured by his family to marry and settle down. Rui, a cheerful and independent woman, faces similar societal expectations. The two meet through a mutual acquaintance and agree to marry, not out of love, but to fulfill societal and familial obligations.

The narrative explores their evolving relationship as they navigate the challenges of living together under the same roof. Initially, their interactions are formal and distant, reflecting their pragmatic approach to marriage. However, as they spend more time together, subtle shifts in their dynamic begin to emerge. Shōta’s quiet dedication to his work contrasts with Rui’s more carefree and spontaneous nature, creating moments of both tension and humor.

Over time, the story delves into their personal struggles and insecurities. Shōta grapples with feelings of inadequacy and the pressure to succeed, while Rui confronts her own fears of vulnerability and the societal stigma surrounding unmarried women. Their shared experiences, from mundane daily routines to significant life events, gradually foster a deeper understanding and emotional connection between them.

Supporting characters, such as Shōta’s colleagues and Rui’s friends, add layers to the narrative, providing external perspectives and influencing the couple’s journey. The manga balances lighthearted moments with introspective themes, portraying the complexities of modern relationships and the societal expectations that shape them.

As the story progresses, Shōta and Rui’s relationship evolves from a contractual arrangement to a genuine partnership. The manga captures their gradual realization that love and companionship can emerge from unexpected beginnings, offering a nuanced portrayal of marriage and personal growth.