Hideki Motosuwa, an impoverished, rural farm boy, fails his college entrance exams and moves to Tokyo to attend cram school. In this futuristic world, personal computers have evolved into "Persocoms"—androids resembling humans that handle everything from daily labor to emotional companionship. Desperate to join the digital age, Hideki longs for a Persocom of his own, but his meager budget makes ownership impossible. His fortunes change when he discovers a female Persocom discarded in a trash heap. Bringing her home and accidentally activating her, he names her "Chii" because it is the only word she can initially speak.Chii’s origins quickly prove mysterious. Unlike standard machines, she lacks an operating system, yet she can learn independently and run complex programs without hardware upgrades. Hideki’s tech-savvy neighbor, Shinbo, and Shinbo’s eccentric teacher, Minoru, analyze Chii and suspect she might be a legendary "Chobit"—an advanced, clandestine model rumored to possess genuine human emotions and free will rather than pre-programmed responses. Meanwhile, a massive search is underway by government agents and mysterious hackers who fear the implications of emotional AI.As Hideki teaches Chii about the world, a deep emotional bond forms. Hideki is fiercely protective, refusing to view her merely as a tool or property, while Chii develops a devoted,
unconditional love for him. This relationship is complicated by the introduction of Freya, a second personality hidden deep within Chii's code. Freya was originally created by the brilliant engineer Ichiro Hibiya as a
surrogate daughter, but she suffered catastrophic emotional trauma and system failure after falling in love with her creator. Chii was subsequently built to absorb Freya’s pain, meaning Chii’s ultimate purpose is tied to tragic heartbreak.Throughout the series, Hideki confronts the ethical boundaries of human-android romance, facing societal stigma and his own insecurities. Subplots explore the poignant realities of other characters, such as Minoru’s grieving android mimicking his deceased sister, and a forbidden romance between a teacher and his student’s Persocom wife. The dramatic climax converges on Chii’s core programming and her feelings for Hideki. When Freya attempts to take over to protect Chii from the pain of unrequited love, Hideki must prove the authenticity of his devotion. Instead of wishing for Chii to love him because she was programmed to, Hideki confesses his feelings regardless of her mechanical nature. This emotional breakthrough forces Freya to reconcile her past trauma and allow Chii to exist on her own terms. Ultimately, Chii chooses Hideki as the person she loves most for who he is, validating the show’s central theme that true connection transcends the barrier between human and machine.