There used to be a cafe called Mon Cheri at Nishi Waseda where members of the Waseda Mystery Club spent day after day frothing in excitement over the latest mystery novels, and now he and Kaede solve mysteries together. As a lover of classic crime stories, it’s perhaps no surprise that twenty-seven-year-old schoolteacher Kaede encounters everyday mysteries more often than your average person. Solving them is another matter, though, and the person she always heads to for guidance is her beloved grandfather who, despite having dementia, retains a keen sharpness of mind. From impossible locked-room murders to confounding missing person cases, the granddaughter and grandfather team ‘weave stories’ in master-and-apprentice fashion to get to the bottom of a variety of cases. All the while, a shadow slowly closes in on Kaede, posing a more insidious threat.