Koyoharu Gotouge Before Demon Slayer: Kimetsu no Yaiba
"There is a human-hunting case which has thrown a town into confusion. The culprit is a vampire...A boy wielding a sword appears in front of the violent vampire?!" - official synopsis (translated) Kagarigari is one of the 70th Shonen Jump Newcomer Treasure Award-winning entries and is the prototype to Kimetsu no Yaiba.
He possesses a mysterious power. His job is to remove curses from others. Whenever abnormal situations arises, Zigzag is called to work. He accepts, however, it's not out of goodwill...? A story about a hero? Definitely not this person!
