Chika and Shun are a newly married couple with a ten-year age gap. Chika fell in love at first sight with Shun, who works at a café, pursued him, and they married. Their life together appears warm and happy, yet Chika cannot shake the growing unease that shadows their relationship: Shun has a childhood friend and first love named Mame, whose presence lingers between them. Chika overhears Shun call out Mame's name in his sleep, deepening her fear that she married a man who is still in love with someone else and that she is merely the person he settled for. Both spouses carry the weight of unrequited first loves. Shun long harbored feelings for Mame, who in turn was in love with Shun's older brother, a widower who never returned her affection. Chika herself experienced a failed confession in her school days. The story traces their efforts to move past these unresolved attachments and build a genuine bond as husband and wife. Their fragile peace is tested by external pressures. A conflict involving Shun's ex-girlfriend forces the couple to relocate to Chika's family home, where her own first love, a neighbor called Goro, still lives. Shun's former classmate Sayaka reenters the picture with renewed romantic interest and deliberately sows discord. Chika, lacking self-confidence, also begins to struggle with anxiety about starting a family and the decision to have children. Further turbulence arises from revelations about Chika's father's past. Through these trials, both Chika and Shun gradually confront their lingering feelings, gain new perspective through small encounters with the people they once loved, and work toward freeing themselves from the past. The narrative concludes with the couple learning that marriage is not a final destination but an ongoing process of building a family together.