Liu Yian, a young man from the south, went to Xi'an to study. He was born with a very yin destiny. As soon as he stepped into the ancient capital of thirteen dynasties, he discovered the secret of the city's twin days and nights. During the day, the world is bustling with fireworks, but at night, ghosts and shadows stalk, and ancient ruins hide evil. One day in the underground ghost town is a year on earth.
He is followed by Ah Nuo, a glutinous rice demon spirit who is both greedy and protective. He also encounters Su Xiaobei, a local girl who is born pure Yang and has a destiny to suppress evil. One yin and one yang, one demon and one person, travel across the city walls, Terracotta Warriors, Huaqing Pool, and Big Wild Goose Pagoda to resolve the obsession of thousands of dead souls and uncover the dusty grievances behind the ancient monuments.
A powerful general in the Qin Dynasty wanted to break the injustice and stir up chaos in Chang'an. During the confrontation, Liu Yi'an awakened to his destiny of guarding the pulse for seven generations, only to realize that he had been bound to this ancient capital for thousands of years.
He does not kill wronged souls, and does not like killing. He re-establishes the order of Yin and Yang with compassion and appeases thousands of lonely souls underground. During the day, he is an ordinary college student, and at night, he is the night watchman of Chang'an. One person, one demon and one beautiful lady, watch over the day and night, changing Chang'an, the ancient capital of thirteen dynasties, every year.
This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.