Waiting for Someone: Spirits of Mountains and Seas

This is a story about waiting.

Tu Shan Yao, the nine-tailed fox, waits for someone who truly loves her, but all she gets is lies and exploitation;

Qing Yu, the Bifang bird, waits for a mate with whom she can join wings, but after three hundred years, their reunion is also their final farewell;

Lang Qi, the great priest of the Skywolf Clan, waits for his daughter to change her mind. After ten thousand years, all he gets is a skeleton saying, "The one you were waiting for was yourself";

The ancient God of War, Xing Tian, sits alone in the wilderness, using his shield and axe to draw someone's likeness on the ground. He spends three hundred years on it, though the person in the portrait has already been reincarnated a hundred times.

And then there is Jiang Liu, an orphan who has been able to see spirits and monsters since childhood. Carrying a piece of broken jade, he is swept into this wait spanning ten thousand years.

He travels from South Mountain to West Mountain, from Qingqiu to Kunlun. He witnesses the nine-tailed fox's tears, the Bifang bird's obsession, the loyalty of the Kai Ming Beast, the fury of the He Luo Fish, the protection of the Ba Snake, and the sacrifice of Yu Shi... Each time he meets a spirit or monster, a tale of entanglement between humans and spirits is revealed, and another part of the bloodline sleeping within him awakens. He is half human, half fox. His father is trapped in the deepest part of the Kunlun ruins, and has been waiting for him for three hundred years.

But when he finally gathers all the fragments of the Nine Tripods and is about to push open that bronze door, he faces a choice more difficult than finding what he seeks:

Stay in the world of spirits and monsters, reunite with his father, and disappear together in the great calamity that will engulf heaven and earth;

Or return to the human world, carrying all his memories, and live on alone.

Wait for someone for three hundred years, for ten thousand years.

Once they finally come, what then?