S1·E12 Chii Confirms

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.