Shinobu has been raising her only son, Mitsuo, all by herself. - New Year's Day and Golden Week are both ``busy seasons,'' so she has to work, making Mitsuo feel lonely. - One day, the season reaches October, when Shinobu is free from work. - Now that she has a relative break, Shinobu thinks of doing something with Mitsuo to atone for her past sins, but she can't decide what to do. - Shinobu then hears from Mitsuo that there is an event called Halloween in October.