Shinichi Kudou, a high school student of astounding talent in detective work, is well known for having solved several challenging cases. One day, when Shinichi spots two suspicious men and decides to follow them, he inadvertently becomes witness to a disturbing illegal activity. Unfortunately, he is caught in the act, so the men dose him with an experimental drug formulated by their criminal organization, leaving him to his death. However, to his own astonishment, Shinichi lives to see another day, but now in the body of a seven-year-old child. Perfectly preserving his original intelligence, he hides his real identity from everyone, including his childhood friend Ran Mouri and her father, private detective Kogorou Mouri. To this end, he takes on the alias of Conan Edogawa, inspired by the mystery writers Arthur Conan Doyle and Ranpo Edogawa. Shinichi, as Conan, starts secretly solving the senior Mouri's cases from behind the scenes with his still exceptional sleuthing skills, while covertly investigating the organization responsible for his current state, hoping to reverse the drug's effects someday.

Rentarou Aijou has it all: looks, intelligence, athletic skill, and popularity with peers and mentors alike. Unfortunately, none of these qualities help Rentarou with his love life. On the day of his middle school graduation, he is once again turned down by a girl he confesses to, earning his one-hundredth rejection in a row. Down on his luck, he goes to a matchmaking shrine and wishes to finally get a girlfriend in high school. When the god of the shrine suddenly appears before him, Rentarou is told he will meet an astronomical total of one hundred soulmates in high school. Though Rentarou initially does not take this foretelling seriously, his doubts disappear when, on the first day of school, he meets two of these soulmates—Hakari Hanazono and Karane Inda—who both confess to him. With fated encounters and love confessions galore, Rentarou's life is about to get a lot more exciting.

The nation of Tempest is in a festive mood after successfully overcoming the surprise attack from the Falmuth Army and the Western Holy Church. Beyond the festivities lies a meeting between Tempest and its allies to decide the future of the Nation of Monsters. The aftermath of the Falmuth invasion, Milim Nava's suspicious behavior, and the disappearance of Demon Lord Carrion—the problems seem to keep on piling up. Rimuru Tempest, now awakened as a True Demon Lord, decides to go on the offensive against Clayman. With the fully revived Storm Dragon Veldora, Ultimate Skill Raphael, and other powerful comrades, the ruler of the Tempest is confident in taking down his enemies one by one until he can face the man pulling the strings.

Yuusuke Yotsuya has always disliked Tokyo, but he especially hates the people who live in it. He would rather thrive in a virtual world than try to get along with those around him. At the end of one school day, he sees the popular athlete Iu Shindou talking to Kusue Hakozaki, who spends less time in school due to illness. But when he looks away from the two and back again, they have seemingly disappeared. Mere moments later, Yotsuya enters a state of free-fall, and the world begins to change around him. Dropping into a large pool of water, the first thing he sees when he comes to his senses is an assortment of enormous monsters. He soon finds out that he has been brought into a game world by Shindou and Hakozaki and that he must complete a quest within 14 days. There is one thing that separates this world from the real world: anyone who dies will be brought back to life in 30 seconds as long as one party member is alive. Tasked with numerous quests that increase in difficulty over time, Yotsuya, Shindou, and Hakozaki attempt to discover the mystery behind the perplexing game world.