Birthday: October 8

Current head of the Lan clan. Lan Wangji's older brother - together, they are known as the Twin Jades of Lan. Warm and refined, sincere and gentle. Looks very similar to Lan Wangji but has darker eye color. Swore an oath of brotherhood with Nie Mingjue and Jin Guangyao.

Lan Xichen has a kind and gentle personality. He tends to wear a smile on his face, and is polite to everyone he meets. In contrast to many in their cultivation society, Lan Xichen treats everyone with the same courtesy regardless of status. For instance, he gladly accepts the tea Jin Guangyao offers him when others refuse to accept anything from the son of a prostitute. Slow to anger, Lan Xichen is only provoked if the situation involves someone he loved, such as when he becomes angry at the thought that Wei Wuxian has deliberately mocked Lan Wangji's feelings.

(Source: Mo Dao Zu Shi wiki)