What was Ma Xian's identity on the first day?

Kyubi no Youko Firefox. According to the brief introduction of the query novel Fate Comes Out of the Horse Fairy, the protagonist Kyubi no Youko Huo Ling Fox, who was all-powerful in his last life, was reincarnated in this life and was born with the mission of rejuvenating the demon race and defending the world. Under the guidance of two masters, he embarked on the road of upholding justice, punishing evil and promoting good.