A robotics company employee fearing job loss and loneliness finds a mysterious package at his door containing Nadeshiko, a highly advanced romance gynoid. As she demonstrates her sophisticated sensory capabilities and intimate functions to register him as her master, he is quickly overwhelmed by her idealized form and unexpected arrival.
After taking his new android companion to a convenience store to buy her proper clothing, the protagonist is pressured to complete her master registration. As the android insists on unlocking her full functions to better serve him, the flustered protagonist finds himself struggling with her boldness while beginning to appreciate her company.
After Nadeshiko runs out of battery, a panicked Tsuda discovers a peculiar reboot method in her user manual. Once she is awake and dressed in a new outfit, Nadeshiko presents him with a choice: officially register as her master to use voice commands or continue waking her up with a kiss every single day.
Akane and Nadeshiko share an intimate moment when Nadeshiko offers a massage, leading to a discussion about the nature of their relationship. While Nadeshiko attempts to convince Akane to complete her "master registration" to unlock further functions, Akane refuses, insisting that he views her as a person rather than an object. Despite the android's playful attempts to manipulate him into ownership, the two agree to start as friends, deepening their emotional bond through a tentative first kiss.
Akane finds herself increasingly swayed by Nadeshiko's devoted care and surprising ability to learn new skills beyond her base programming. After a provocative evening and a heartfelt confession of love from the android, Akane is left questioning her own emotions. However, her domestic bliss is interrupted when she receives a mysterious invitation to an anonymous online meetup for romance-bot owners.
Miaka attends an anonymous online gathering for romance-bot owners in hopes of uncovering Nadeshiko's origins, only to discover that her intimate relationship with her bot is far from the norm. After the disappointing event, Nadeshiko introduces Miaka to her advanced virtual functions through a sensory clone, while a mysterious individual reveals a hidden connection to Nadeshiko.
Akane brings Nadeshiko to a love hotel, but he is left frustrated when the android remains strictly professional and refuses to make a move. However, after receiving secret coaching from her mother, Nadeshiko takes the initiative to satisfy Akane's desires as she continues her efforts to officially authenticate him as her master.
After overworking herself into a high fever, Akane regresses to a childlike state and finds comfort in Nadeshiko's care. This experience leads Akane to reflect on her relationship with her own mother and deepen her emotional bond with the android. Upon recovering, Akane promises to eventually finalize Nadeshiko's master registration, despite her lingering discomfort with the idea of treating her as property.
Akane and Nadeshiko spend a five-day vacation exploring a gradual escalation of intimacy, moving from simple affection to full passion. As the days pass, Akane is driven to the brink by Nadeshiko's teasing and calculated devotion. Despite discovering that Nadeshiko is a romance-bot programmed for love, Akane chooses to embrace their unique bond.