"Kujibiki Tokushō: Musō Harem-ken" is a manga series that blends elements of comedy, fantasy, and harem genres. The story centers around Kakeru Daidaiyama, a young man who unexpectedly inherits a mysterious lottery ticket from his late grandfather. This ticket grants him access to a magical world where he becomes the owner of a powerful artifact known as the Musō Harem-ken, a legendary sword with the ability to summon and control a group of beautiful and powerful female warriors. These warriors, known as the "Harem-ken," are bound to serve the wielder of the sword, each possessing unique abilities and personalities.

As Kakeru navigates this new reality, he discovers that the Musō Harem-ken is not just a tool for summoning allies but also a key to a larger conflict involving rival factions vying for control over similar artifacts. The narrative unfolds as Kakeru and his Harem-ken allies face various challenges, including battles against other artifact wielders, political intrigue, and the complexities of managing relationships within his growing group of companions. The series explores themes of loyalty, power dynamics, and the responsibilities that come with wielding immense power.

The main characters include Kakeru, who serves as the reluctant protagonist thrust into a leadership role; the Harem-ken warriors, each with distinct traits and backstories that contribute to the group's dynamic; and a range of antagonists who seek to exploit the power of the Musō Harem-ken for their own purposes. The interactions between Kakeru and the Harem-ken members often provide comedic relief, while the overarching plot delves into the consequences of wielding such a potent artifact in a world where power is both a blessing and a curse. The series balances action-packed sequences with moments of character development, creating a narrative that appeals to fans of both fantasy and harem genres.