Shinobu is a mother who has raised her only son, Mitsuo. Due to her demanding job, she often had to leave Mitsuo feeling lonely during busy times like New Year and Golden Week. As the season changed, October arrived, bringing a lull in Shinobu's work schedule. With more free time on her hands, she began thinking of ways to make up for her past absence by spending quality time with Mitsuo. However, she struggled to decide what they should do together. That's when Mitsuo told her about Halloween, an event celebrated in October, sparking an idea in Shinobu's mind to come up with a special plan.