Chii isn't feeling like herself and basically collapses in Hideki's apartment. He gets an adapter from Shinbo but unfortunately can't recharge Chii due to the fact that he never paid his electric bill.

He struggles to find a building to recharge Chii but falls when climbing a wall to a building which is open til 2am. Luckily for him Ms. Hibiya saw them froma cab window and allowed Hideki to charge Chii from her place. Shinbo arrives and informs Hideki and Ms. Hibiya of how many watts are being used to recharge Chii. Hideki exclaims that he will pay her back for both the electricity used and his rent even if it kills him.

Hideki is scared of a room in the apartment because of a horror story he heard at Minoru's house when he was asking about the internet through Minoru's custom-made Persocom Yuzuki. He becomes paranoid thinking about the story and, believing that his apartment building is haunted, has several self-induced hallucinations. The apartment number in the story is 104, as 4, or shi. "Shi" is the Japanese word for Four (四) and Death (死), and because of this, the number four is unlucky in Japan. According to the story, a woman who was hoping to rendezvous with her lover was killed in that room. Hideki and Chii along with Shinbo, Minoru and Yuzuki decide to investigate. At the end, Hideki and Chii discover that it is all a misunderstanding.

Hideki discovered that Shinbo and Ms. Shimizu on the street hugging each other. The next day, Shinbo and Ms. Shimizu aren't at class. And then Sumomo is left in Hideki's care! Could something be up with those two? And isn't Ms. Shimizu married?

While Chii is on her way to work, she notices the third part of the book series "A City With No People" on the shelf of a bookstore. While she flips through the pages, she is grabbed from behind and is kidnapped. Hideki comes home from prep school and returns to find Chii missing.

Chii is still missing, and Hideki is enlisting as much help as he can to find her. A strange e-mail image gets sent to him and Shinbo from an untraceable email address. It turns out that this is a map for the house of Chii's abductor, Dragonfly, and he is carrying out research to find out what Chii is.