My Five Thousand Year Old Taoist Companion

Bai Jie inadvertently traveled to a magical world where magical skills were practiced everywhere, but no one learned them. Then he was inadvertently sent to the realm of the demon god and became an apostle of the demon god of knowledge. In the end, when he came out, he accidentally resurrected the Red God who died five hundred years ago. Because the Red God had nothing, he gave himself to Bai Jie in return.