Ren Amamiya awakens in a reality that defies logic, realizing he has been reborn into a comprehensive world where the plots of countless anime series intertwine. Armed with the meta-knowledge of a former fan, he identifies his location as the dangerous Beika City, infamous for its high murder rate, and recognizes the school he attends as Teitan High. To survive the looming threats of organized crime and supernatural detectives, Ren activates a mysterious cheat: a diary that exposes his inner thoughts directly to specific heroines across different storylines.

As he chronicles his strategies to avoid becoming a plot casualty, his words inadvertently guide characters like Nagi Sanzenin, altering their fates and drawing them into his orbit. While attempting to maintain a low profile as an ordinary part-time worker, Ren finds himself becoming the unseen architect of events, balancing the absurdity of multiple colliding universes with the very real danger of the God of Death lurking around every corner.