Demon Slayer: The Tainted Sun

Tanjiro Kamado was attacked by Muzan on his way home and turned into a demon. He manages to regain his humanity, but is soon decapitated by Water Hashira, Giyu Tomioka. However. Tanjiro regenerates for unlike every other demon, he was resistant to sunlight. After running away from home, Tanjiro must adapt to life as a demon while avoiding both Muzan and the Demon Slayer Corps.