Let's just say I got hooked. The series starts off with an entertaining introduction of Hideki Motosuwa, a farm boy-gone-college prep student who buys a new apartment in Tokyo. Immediately he's immersed into a new and surprising world filled with persecoms-humanoid computers who carry out amazing tasks for their owners: email, phone calls, list making, schedules, education, entertainment, careers, labor, etc. Unexpectedly, he discovers a persecom lying in the dumpster outside his apartment, and after discovering a peculiar "on switch" between her legs, he is able to reboot her. The persecom is eventually found to be quite unusual-she has no memory, no accessible operating system, she crashes every persecom she is connected to, and she has no sense of vocabulary or knowledge of everyday tasks. Much of the season follows the pair as Hideki attempts to teach Chi how to operate in daily life while juggling a job and studying at prep school. In addition, he tries to find out more about her origins and inner workings with the help of some tech-savvy friends, who suspect Chi could possibly be a Chobit-A legendary persecom possessing true emotions and therefore is fully sentient. As the plot progresses Hikedi's feelings towards the dynamic, innocent Chi complicate as he finds it harder and harder to think of her as "just a machine" and she constantly strives to make Hideki happy. This inner turmoil is further delved into as Hideki discovers the persecom-tangled pasts of his friends and their individual coping with emotional connections to humanoid computers. After several mishaps, mysterious images, and messages from a strange picture book that seems to be written about Chi, it becomes evident that the rare persecom is very special indeed. A theme begins to hover around Chi and her past: a need to find true love, the one "for me and only me." It is soon revealed that Chi had a twin sister created in her past life by the creator of all persecoms, who made these two "daughters" for his wife-now a landlady at Hideki's apartment builiding. Freya, the first daughter, was made with the capacity to find true love and subsequently falls in love with the man who created her, which causes her so much sadness that a sister is created named Elda, now called Chi. Even so, Freya soon dies of sadness; Chi takes Freya's heart and memories inside her body and soon crashes herself, begging to start a new life where she can find her true love. If she fails, her creator gives her a gift: a program that will destroy the face-recognition of all persecoms so that they will never feel the anguish of unrequited love. The drama climaxes when Chi, told by Freya within her-and Hikedi, told by the landlady, both discover Chi's past. Chi asks Hideki if she is the one for "Hideki and only Hideki" and he hesitates to reply, thinking carefully.
Here the plot splits. In the manga, Hideki says yes and Freya suddenly takes Chi's place, asking Hideki if he also "wants" Chi. She then warns him that he will never be able to make love to Chi because of the location of her rebooting switch, and Hideki says he cares about Chi too much to let that setback affect his love. Freya becomes Chi again and the program does not have to be run, letting Hideki live happily ever after with Chi and giving hope for love to all other persecoms.
In the anime, there is no mention of the rebooting switch, but previous lines (appearing both in the manga and anime) such as "only the one for me and only me can come inside" makes the reader/watcher question whether Hideki will be able to love Chi with both heart and body; however there is no clear answer. When Hideki tells Chi that he requites her love, she rises into the sky and begins to start a program; in the anime, there is another aspect to the gift the creator gave her that one assumes will better all persecoms. When she is attempted to be stopped by a government security persecom Chi shuts down and Freya takes over, explaining that Chi had doubts and canceled the program. Seeing the mission had failed, the landlady clears all data from the persecom, much to the despair of Hideki, and plans to destroy the late Chi/Freya. However, as they are walking away, Hideki talks about how much he just wanted Chi to be happy, and somewhere inside she hears and returns to her body. With this joyous event the program is run and every persecom in the world is given the gift to truly love and find love, and there is still the happy ending.