The Loyal Hound's Eternal Vow

A dog demon named Ah Huang guards his master's grave for a hundred years, waiting for his master to be reincarnated as Ah He, only to witness Ah He being abused to death by her husband and mother-in-law. Ah Huang possesses a corpse to return to the living world, raises Ah He's children Shitou and Sui'er as their mother, avenges Ah He, then guards the village, protects women and children, diverts water from thousands of miles away during a severe drought, and summons packs of dogs to protect villagers during war. A hundred years later, Ah Huang is awakened in modern times by a little girl who looks exactly like Ah He did in childhood, and realizes he has become a patron deity worshipped by generations.