The story begins on a winter day, just as our protagonist Totono Kuno is preparing a warm curry dish. While chopping onions, he is unexpectedly visited by the police, who politely ask him to accompany them to the station as a suspect in a nearby murder.

To his surprise, the victim turns out to be a former high school classmate. As detectives begin laying out their evidence against him, Totono's calm and analytical nature shines through. Using only logic and observation, he begins unraveling the mystery. But what will happen to him next?