Demon Slayer: Kimetsu no Yaiba is a Japanese manga series written and illustrated by Koyoharu Gotōge. The story follows Tanjiro Kamado, a young boy who becomes a demon slayer after his family is slaughtered and his younger sister Nezuko is turned into a demon.
It has been serialized in Weekly Shōnen Jump since February 2016, with its chapters collected in 19 tankōbon volumes as of February 2020.
In Taishō-era Japan, Tanjiro Kamado is a kindhearted and intelligent boy who lives with his family. He has become his family's sole source of income after the passing of his father. Everything changes when his family is attacked and slaughtered by a demon.
Tanjiro and his sister Nezuko are the sole survivors of the incident, with Nezuko being transformed into a demon, but still surprisingly showing signs of human emotion and thought. After an encounter with Giyū Tomioka, a demon slayer, Tanjiro is recruited by Giyū to also become a demon slayer, which begins his quest to help his sister turn human again and avenge the deaths of the rest of his family.
At the end of February 2020, it was revealed that the franchise has sold 40.3 million copies, making it the 5th best selling manga in Oricon's history. It was the best-selling manga in 2019, and the first series to take all top 10 positions of Oricon's weekly manga chart.
In February 2020, volume 19 of the series sold an estimated 1.378 million copies in its first week, making Demon Slayer: Kimetsu no Yaiba the third manga series to have a single print volume sell more than 1 million copies in its first week, after One Piece (45 times) and Attack on Titan (2 times).
According to animenewsnetwork.com and en.wikipedia