I am a demon slayer

I am the magical companion to the Demon King, born with a frail body, appearing like an ordinary human. In an effort to protect my master, I even injured my head, forgetting everything from my past. Fortunately, Xie Jinglan cherished me deeply, showing me exceptional tenderness. That was until the Priestess, Liu Yiyi, was found and returned. He indulged her as she tore apart the colorful feather robe gifted for my birthday, destroyed the sacred herbs vital for my recovery, and threw me into the Den of Beasts for eighty-one days, where I suffered the agony of being torn by fierce creatures. At the brink of death, a revelation struck me—I am the foremost demon slayer of the Nine Deer Realm.