This manga adapts the sixth game of the Umineko WHEN THEY CRY mystery, in which Battler Ushiromiya takes over as Game Master and has to build his own board to show he understands Beatrice's puzzle of the Rokkenjima murders. A Beatrice reborn without her old memories stands at his side, timid where she was once fierce. Facing him again is the detective and witch Erika Furudo, who takes apart every claim he makes with cold logic.