Socially exhausted from three years of relentless office work, salaryman Amae Yuuya lives a hollow, convenience-store-meal routine. One evening, a knock at his door brings an unexpected visitor: Shiratori Aoi, the eight-years-younger girl who used to live in his neighborhood and whom he has not seen in seven years. Now a high school girl skilled at household chores, Aoi wastes no time in declaring her lifelong crush and proposing marriage on the spot. Bewildered but unable to turn her away, Yuuya reluctantly agrees to let her stay under the pretense of acting as her guardian. The cohabitation that follows is anything but platonic: Aoi showers him with affectionate care and bold romantic advances, steadily chipping away at his worn-out demeanor and forcing him to confront feelings he had long buried.

The story unfolds against the backdrop of Yuuya’s modest apartment, where the daily rhythm of shared meals, small errands, and quiet evenings begins to revitalize him physically and emotionally. As his energy returns, his work performance improves, and he grows increasingly aware of his own attraction to Aoi. The narrative arc tracks the progression of their relationship from a guardian-ward setup to genuine mutual love. Key milestones include a Christmas date that marks their transition to an official couple, a company trip where Yuuya finally confesses his feelings, and a Valentine’s Day surprise that puts his self-control to the test. Later storylines introduce Aoi’s university ambitions: Yuuya supports her through open-campus visits and prep-school costs, while Aoi’s affectionate advances grow bolder as their bond deepens. The volume culminating in a photo-wedding proposal marks Aoi’s high school graduation and hints at the couple moving toward a more permanent future.

The main characters anchor this gentle romantic comedy. Yuuya is a diligent but drained office worker who rediscovers purpose and vitality through Aoi’s unwavering devotion. Aoi is a capable and earnest young woman who, despite being somewhat bad at relying on others, dotes on Yuuya with wholehearted dedication. Supporting cast members include Kanbe Rumi, Aoi’s lively gal-type friend who cheerfully intrudes into their domestic life; Tsukishiro Chizuru, Yuuya’s reliable and heavy-drinking boss who offers comedic yet sage advice; and Rumi’s younger sister, whose innocent antics occasionally spark playful rivalries for Yuuya’s attention. The narrative’s central tension lies in Yuuya’s internal struggle to reconcile his role as a responsible adult with the rapidly growing romantic and physical intimacy that Aoi openly pursues. The series thus offers a warm, low-drama exploration of age-gap romance, domestic healing, and the journey from weary solitude to shared happiness.