Chang An is Zhuang Cheng's only friend at university. He is concerned about Zhuang Cheng's obsession with urban legends and once tried to persuade him to stop, fearing that Zhuang Cheng might break the law. He is a supportive but cautious friend. Later, he seeks out Zhuang Cheng because he has encountered something unexplainable himself, showing that he trusts Zhuang Cheng's expertise in strange matters. He appears frightened and burdened when he visits, hinting that he has recently experienced a terrifying incident.
