Taiga Shishiyama is a struggling freeter searching for employment when, at the brink of death, he's suddenly summoned to another world. There's just one rather significant difference between this world and his own: there are no men. Taiga is now the only man alive. With humanity facing eventual extinction, the people of this world haven't summoned Taiga to defeat a Demon King. Instead, they expect him to become their new king and choose a queen. Waiting for him are eighteen bridal candidates drawn from every corner of society, differing wildly in age, profession, social standing, personality and even race. Taiga must get to know them, survive a series of trials alongside them and ultimately select just one woman as his bride. Unfortunately, what should be an intensely personal decision has become the biggest entertainment event in the entire kingdom. The public eagerly follows the competition, the candidates are eliminated as the trials progress, and Taiga himself is forced to decide which women will lose their chance at becoming queen. As romantic rivalries develop and Taiga begins forming genuine feelings for the candidates, the competition also reveals that not everyone supports the queen-selection process. A mysterious thief targets the world's only man, opposition to the selection begins moving behind the scenes, and secrets surrounding the disappearance of men from this world threaten to turn the royal marriage contest into something considerably more dangerous. An isekai harem romantic comedy where eighteen women compete for the heart of the only man in the world, and he must choose just one to become his queen.