Nagaharu Murai

Nagaharu Murai is the owner of the CDV video rental store. He is an always smiling middle-aged man in his fifties, perpetually seen wearing a polo shirt, though with a different color each time, as well as a gold wristwatch. He never remembers his employees names, always looking at their name tags, and always refers to people using the suffix -shi (氏). Whenever he shows up at the CDV store, he gets Tokuma and Shingo to recommend him movies, always either historical dramas or suspense flicks. Rumored to have been a gambling expert hired by the yakuza, Nagaharu possesses the skill to instantly and with 100% accuracy predict the culprit behind an incident the moment he looks at them, even at a photograph.

He is revealed to be the true culprit behind the case. He is an assassin sent by the Keisatsukan (刑殺官) to execute all 101 members of Shinozuka Takashi's secret dating club organization, most of whom are students of Seikou Private Girls' Academy, disguising their murders as suicides. Also known by the codename Papa and as the Scarlet Samurai (緋色のサムライ), he leaves various clues to his identity in the form of wordplays. Eventually, after revealing his identity to Shingo and upon failing to assassinate Yagiri Saki, Nagaharu himself turns up dead, seemingly having committed suicide, though Shingo theorizes that he may have been silenced.