Taking place 2-3 years prior to "Spiral - Suiri no Kizuna," this story serves as a prequel and follows Imari, the protagonist who has developed feelings for a promising detective. However, Imari is unaware that his love interest is romantically tied to a serial killer and ends up leaving school to chase after him. As the plot unfolds, we see how this story links to the Blade Children and how Kiyotaka's control over them impacts the narrative.