Blackmailed into playing a dating simulator set in a matriarchy, an ordinary man must put up with the unbearable and convoluted world until he clears the game. After countless days of grinding, he finally manages to beat it, but his hardcore gaming comes at a cost: extreme sleep deprivation and hunger. While heading out to the convenience store to solve one of these problems, the man tumbles down the stairs and falls unconscious, only to wake up to the worst possible realization—he has been reincarnated into the game as the mob character Leon Fou Bartfort. Now trapped in a world he despises, Leon must use his knowledge of the game to navigate through the plot safely and sustain himself in a society where the odds are heavily stacked against him.

Shaped by experiences that left him weary of human relationships, Rei Hitoma openly dislikes people. Seeking a quiet, uneventful life, he accepts a teaching position at a secluded school in the mountains, only to discover that his classroom is anything but ordinary. The students under his care are demi-humans who have gathered there with a singular goal: to learn what it means to become human. Despite his disillusionment, Rei finds himself responsible for explaining human behavior and social norms to mermaids, bunnies, werewolves, and the like. As his students earnestly struggle to understand humanity, their questions and aspirations gradually expose the contradictions in Rei's own beliefs.

Through their tutor Fuutarou Uesugi's diligent guidance, the Nakano quintuplets' academic performance shows signs of improvement, even if their path to graduation is still rocky. However, as they continue to cause various situations that delay any actual tutoring, Fuutarou becomes increasingly involved with their personal lives, further complicating their relationship with each other. On another note, Fuutarou slowly begins to realize the existence of a possible connection between him and the past he believes to have shared with one of the five girls. With everyone's feelings beginning to develop and overlap, will they be able to keep their bond strictly to that of a teacher and his students—or will it mature into something else entirely?

Having reached the pinnacle of human potential, Varvatos was so powerful that the rest of humankind began calling him the Demon Lord, both fearing and respecting his overwhelming influence. As a result, he felt alienated from his fellow humans, leading him to desire true companionship—an equal he could call a friend. Hoping his fate will change in his next life, Varvatos decides to start anew and reincarnates three thousand years later as Ard Meteor, the son of a seemingly ordinary couple in a rural town. Unfortunately, he realizes that even after weakening himself, his strength still overshadows everyone in this era. Moreover, his lack of social skills bars him from achieving his goal of making friends. But worst of all, the repercussions of suddenly abandoning his former position have begun to bite him back in some of the most unimaginable ways possible.