"I Got Caught Up In a Hero Summons, but the Other World was at Peace" centers around Kaito, an ordinary high school student who is unexpectedly summoned to another world. Unlike typical isekai narratives, this world is not plagued by chaos or a demon lord; instead, it is a peaceful, thriving society. The summoning ritual, intended to call forth a hero to save the world, was performed by the kingdom of Reijseger, but due to a misunderstanding, Kaito is brought instead of the intended hero. Despite the lack of immediate danger, the kingdom decides to honor the summoning and treats Kaito as their hero.

Kaito is introduced to the royal family, including the princesses Lilia and Elise, who are tasked with assisting him. The story explores Kaito's adjustment to this new world, where he is revered as a hero despite his lack of extraordinary abilities. The narrative delves into the political and social dynamics of Reijseger, as well as Kaito's interactions with its inhabitants. The kingdom's peacefulness allows the story to focus on character development and world-building rather than traditional conflict-driven plotlines.

As Kaito navigates his new role, he forms bonds with various characters, including the princesses, knights, and other summoned individuals. The series emphasizes themes of responsibility, identity, and the meaning of heroism in a world that does not require saving. Kaito's journey is less about battling external threats and more about understanding his place in a society that views him as a symbol of hope, even in the absence of crisis. The manga balances lighthearted moments with introspective elements, creating a unique take on the isekai genre.