Uzumaki Nanami, twin sister of Uzumaki Naruto and student of Lady Tsunade, Died trying to protect her brother and friends during the fight with Kaguya Otsutsuki. However she didn't end up going to the after-life as she think, instead the sage of six paths assigned her a mission which cause her to go to another world where man-eating demons prowl around Japan in the Taishō era. Her mission was to protect a burgundy-haired boy, by the name of Kamado Tanjiro, and to defeat the demon responsible for the deaths of many people. In her arrival, she was fortunately taken in by the Kamado family for few months before tragedy struck. While she was out with Tanjiro, his family died by a demon and his younger sister Nezuko turned into a demon. They soon made their way to become a demon slayer to avenge the deaths of the people they cherished and turn Nezuko back into a human. Along the way, they meet friends and comrades but also love. How will they take when Nanami showed her abilities as an Uzumaki and student of the legendary sannin herself? Read to find out, dattebane! I DO NOT OWN KIMETSU NO YAIBA OR NARUTO SHIPPUDEN EXCEPT FOR MY OC!!!