An ordinary salaryman named Yuuto Aida comes home to find his wife in bed with another man. Stunned and furious, he bolts out of the house only to be struck by the proverbial truck and killed. He awakens in a fantasy world where he is slated to become a legendary hero. But a blunder by the reincarnation goddess leaves him with only a single skill: Complete Married Woman Charm. In this world, every married woman he meets becomes irresistibly drawn to him. Yuuto decides to embrace his bizarre new power and sets out on a journey, recruiting a party composed entirely of wives who fall under his spell.

His first companions are Matiluna, a thief, and Quinn, a martial artist. Together they travel through various lands, quickly learning that the charm crosses racial boundaries when it works on a dark elf wife in a hidden village. In need of a healer, Yuuto recruits Olga, a stern-looking priestess at a convent, who turns out to have a hidden past and a fiery temperament beneath her holy robes. To cover long distances the party seeks a carriage from Ibiza, a wealthy merchant who is also a married woman and quickly becomes another of Yuuto's conquests. The group then encounters Tomoe, a samurai and descendant of a legendary hero. Because she is unmarried, Yuuto's skill initially has no effect, but when Tomoe's childhood friend proposes and she accepts, she becomes a wife and falls under the charm, unlocking a new power for Yuuto in the process.

The party continues to grow as they acquire better equipment, explore dungeons for legendary weapons, and finally secure a ship by charming a pirate named Seagull, who had been coerced by monsters to save her child. Crossing to the demon continent, Yuuto faces his greatest shock: the Demon King is a beautiful married woman, and her husband, the Great Demon God, is sealed beneath the world. Yuuto's charm works on the Demon King as well, and she falls for him completely. A married-woman council is held to devise a plan to defeat the Great Demon God, and the party decides that the seven wives will take turns spending intimate nights with Yuuto to raise his level all the way to 99. With their combined strength and his unique ability, Yuuto leads his unconventional harem of guided wives toward a final confrontation with the ultimate evil.