Matsumiya Kanas world is flipped when her father is arrested for embezzlement from the Ministry of Defense. To cope with the trauma, she transfers to a private boarding school. However, trouble arises as she discovers that Kisaragi Kou, who helped her open up, may not be who he says he is. Additionally, there's a mysterious figure in a trucker's cap lurking outside her window. Welcome to C-blossom -case729-, a series filled with action, intrigue, and a captivating plot.