Yuki has become a bit more optimistic, thanks to Hikari and Machi. She's learned to trust Tetsuo a bit more since what happened last time, and has decided to tell her what troubles her about her own nature as a snow woman. It began shortly after she moved to a new city to start high school, when she was taking a bath one day and a shard of ice suddenly appeared in the hot water. It made her worry about what would happen if the cold air she generated were ever to be directed at a person, which led to her decision to avoid contact with others.
The story takes place in an age where "Ajin" (demi-human), more casually known as "Demi," have slowly started to become accepted into human society. Tetsuo Takahashi is a biology teacher who ends up teaching three such Demi, hoping to understand more about them while also managing to catch their attention.
