While he was practicing boxing, Kubo Masaru was seriously injured and became unconscious . Fortunately, he recovered from the injury, but he couldn't continue boxing anymore. When he visited sanatorium for rehabilitation, he met his classmate, Ouse Yumiko.

Unable to break her desire for Masaru, Maki heads to the summerhouse with him. At the same time, the robbers who kidnapped Akira were nearing in on the location.