Chico Kawaguchi, a 20-year-old woman living in Osaka, lost her only relative, her father and suddenly became lonely for the rest of her life. When Chico, who was exhausted mentally and physically after the funeral, woke up the next morning, there was a strange woman in the house. She called herself Tomo-chan and claimed that Chico's father, who she met on a mobile phone site, wanted her to come to his house for his daughter who has no friends and that she will live with her. From that moment Chico, who became hikikomori and has no education and general knowledge and Tomo-chan, a mysterious woman, started their strange cohabitation.