Flame Breathing (炎の呼吸,Honō no kokyū?) is one of the five main Breathing Styles directly derived from Sun Breathing. The Breathing Style of the Flame Breathing seemed to have been developed by a distant ancestor of the Rengoku Family, who was originally a student of Yoriichi Tsugikuni. It can be assumed that this student attempted to master the Sun Breathing but, due to him not being as innately powerful as Yoriichi, his teacher altered his Breathing Style training in order to better focus on his students individual strengths and weaknesses. Eventually, his student continued to develop and train this style until it became its own unique breathing and was subsequently named the Flame Breathing. Since then, this particular Breathing Style has been passed down and taught through generations of his descendants and the future members of the Demon Slayer Corps.