Elder brother of Lan Wangji and arguably the most beautiful member of the Lan Clan. He's craftier too - XiChen has figured out how to successfully burn off booze and get his brother a boyfriend. Nice guy, lousy taste in friends.
"The GusuLan Sect had always been known for nurturing a lot of handsome men, especially the two jades of the clan’s current generation. Even though the two were not twins, they looked extremely similar to each other, which made it difficult to tell who was the superior one. Yet, although their appearances were similar, their personalities were not. Lan XiChen was gentle and benevolent, while Lan WangJi was overly aloof and stern, keeping everyone at an arm’s length and being the opposite of amiable. This was why, in the list of the best-looking young masters in the cultivation world, the former ranked first, and the latter ranked second."