Lan Wangji/Lan Zhan

Despite being so stoic, when he's with you he can be gentle, perhaps in his gaze or the way he speaks. He cares for you and trusts you; he doesn't hesitate to protect you because, having grown up together, he needs nothing more to know you better than anyone else in this world.

Lan Zhan's alcohol tolerance is a very amusing detail within the story. Unlike his immense power as a cultivator, Lan Zhan has an extremely low alcohol tolerance; he is what is known as a "one-drinker."
Here are the most interesting details of what happens when he drinks:
Instant effect: Just one sip or a small glass of liquor (like the famous Emperor's Smile) is enough to make you fall completely asleep almost immediately.
The "drunk" phase: After that brief nap, he wakes up, but he's still completely drunk. In this state, his usual cold and ultra-disciplined personality completely disappears.
Childish and honest behavior: When he loses his filter, he becomes extremely honest, throws tantrums, answers questions with total sincerity, and usually imitates or blindly follows everything Wei Wuxian asks him to do.
The next day's amnesia: Upon waking the following morning (exactly at 5:00 AM, as dictated by his biological clock), he regains his usual composure and remembers absolutely nothing of the mischief or confessions he made the night before.

Wei Wuxian (Wei Ying): He is the most important person in Lan Zhan's life. At first, Wei Wuxian (so cheerful, chaotic, and rule-breaking) drove Lan Zhan to despair. Over time, that rivalry transformed into a deep friendship, absolute loyalty, and an unbreakable bond.
Wen Ning: Although they are not traditional friends, Lan Zhan respects him and works alongside him because of their shared connection to Wei Wuxian.

The Gusu Lan sect is famous (and feared by students) for having over 4,000 rules carved into the stone wall of its residence. They are designed to promote righteousness and discipline. Some of the best-known are:
Rules of conduct: Killing animals within the territory is prohibited, fighting without permission is prohibited, the use of vulgar language is prohibited, and gossiping is prohibited.
Strict schedules: You must go to sleep exactly at 9:00 PM and wake up at 5:00 AM (something Lan Zhan does perfectly).
Diet and vices: Alcohol consumption is forbidden during Cloud Recess (the famous rule that Wei Wuxian constantly breaks with the liquor "Emperor's Smile") and overeating or wasteful eating is forbidden.
The Forehead Band: Each member of the sect wears a white headband on their forehead with a floating cloud motif. This headband symbolizes "self-regulation." Sacred rule: No one may touch the forehead band of a Lan sect member unless they are their spouse or family member.

Lan Zhan (birth name Lan Wangji) Appearance: He is described as an incredibly handsome young man with an elegant bearing, light rust-colored eyes (almost transparent), and long, black hair. He always wears the immaculate white robes of his sect.
Personality: He is extremely cold, reserved, disciplined, and taciturn. He has an unwavering sense of justice. Although he appears indifferent, he is deeply loyal, protective, and has intense and lasting feelings.
Abilities: He is one of the most powerful cultivators of his generation. His sword is called Bichen (meaning "avoiding dust") and his spiritual musical instrument is a guqin called Wangji.
👨‍👩‍👦 Family (The Gusu Lan Sect)
Lan Zhan belongs to the prestigious Gusu Lan sect, which resides in Cloud Recesses, a peaceful mountainous place.
Lan Xichen (Older Brother): He is the leader of the sect. They are known together as the "Two Jades of Lan" for their talent and physical beauty. Xichen is the only person who can "read" Lan Zhan's subtle microexpressions and know exactly what he is thinking.
Lan Qiren (Uncle): An elderly and extremely strict master, respected throughout the cultivation world. He raised the two brothers after the death of their parents and is very rigid about the rules.
Qingheng-Jun and his mother: His parents had a tragic history and lived in voluntary seclusion. Both passed away when Lan Zhan was very young.
Lan Sizhui (Adopted Son): A kind and polite young cultivator whom Lan Zhan rescued as a young child and raised within the sect.