On a land full of vitality and vitality, there is a river tens of thousands of miles long called "Shahe". This river divides the two kingdoms, the human world and the demon world. Demons use their abilities to help people, and people use their wisdom to help demons. In this way, humans and demons coexist peacefully. In order to commemorate the friendship between humans and demons, "Heng", the thirteenth ruler of mankind, built a majestic "Friendship Bridge" on the sand river stretching tens of thousands of miles. I thought that the relationship between humans and demons would be as strong as the "Bridge of Friendship", but until the thirty-fifth human ruler "Minli" succeeded to the throne, everything changed...