However, according to an insight from the creator, Koyoharu Gotouge, these styles are not real but rather how they are perceived by others and in the imagination of the users. Demon Slayer volumes ...

The legendary swordsman of the Demon Slayer series - Yoriichi Tsugikuni ... Yoriichi was also known to be the creator of the Breathing Styles, and was the first to come up with Sun Breathing ...