Chapter 1: Friend
In the small town of West Yomogi, the young girl Shijima Tsukishima, following a tragedy during her first year of middle school, decides to hide away from society in her apartment's closet for two years. Inside was a small world with nothing but herself, a bookshelf and her bed, all illuminated by a single light bulb.
After two years have passed, Shijima realized she should finally come out to start her term as a first-year student in the West Yomogi High School and take the admission test. As she prepares for her first day and looks in the mirror, however, she notices two shimeji mushrooms sprouting on her head, possibly being some sort of metaphor. Shijima converses with her older sister, who seems to like the thought of living a quiet life similar to her sibling's. The sister was supposed to be attending university, but she dropped out to conduct her research involving a strange machine in the room. Shijima then steps out into the outside world for the first time in two years.
When she reaches the entrance of the school, Shijima plans to make it to her class without drawing attention with her mushrooms, passing them off as hair ornaments. She finds out, though, that she is not the only student sporting peculiar accessories. She quietly arrives at Class 1-D and starts reading the book of The Old Man and the Sea, but, unfortunately for Shijima, a fellow classmate with a half-fried egg on top of her head approaches her in an attempt to strike a conversation. Shijima ignores her, only for the classmate to notice that she also has a food-like object on her head, prompting her to further attempt to befriend her through annoying methods, from poking her mushrooms to shaking her desk, much to Shijima's dismay. Shijima tells her about her unwillingness to form any friendship, calling it a hassle, but the egg girl does not agree with her way of thinking and decides to show her what true friendship is all about. Her attempt at making an example fails badly when she barges into a discussion of Potapotamiya Culture among the group of classmates and gets reprimanded by Ayaka, one of the girls. The egg girl goes to cry on Shijima's desk, and as it turns out, she doesn't have any friends of her own, either.
At the end of the school day, Shijima and her classmate are walking together, with the latter wondering what it means to have friends. Shijima believes that starting friendships are more of a natural occurrence than something you agree upon like a contract, unlike when you ask a partner out on a date. The egg girl imagines that it would be easier to just get a lover than a friend, so she takes the opportunity to ask Shijima out. She immediately agrees, having no choice but to play along with her tiresome antics. The two try holding hands, but Shijima coldly slaps her classmate's hand and walks away. Back at home, Shijima's sister gets surprised by the sudden development of the former social outcast after being flat out told that she "got a girlfriend". That night, Shijima slept soundly without dreaming.
