One of the prides of the Auriel people are the yilan, dancers believed to be human incarnations of cobras. They perform a unique type of dance said to beguile onlookers. The dance is believed to not be learned, but innate. If one needs to learn it, they are not a real yilan. The phenomenon has never been properly explained, but most people would rather believe it's simply a combination of talent, charisma, and being double-jointed. In reality, no amount of training could achieve the inhuman contortions of a true yilan.
As such, they are extremely rare. Most of which are female. A male yilan is said to be a nigh legendary sight. Others say they do not even exist.
Some might have the ability without even realizing it. Their rarity is such that many dancers will pretend to be one, fooling the public. Only those who have ever witnessed the real thing would be able to tell the difference. Due to yilan dancers being so few, many terrifying rumours circulate about them. People say they can turn into a cobra at will. That the mere touch of their skin is poisonous enough to kill. That they can hypnotize with their stare. That their enchanting beauty has caused the ruin of empires.
These are, of course, only rumours. Although the one about poisonous skin one could stem from Auriels' blood being highly toxic. But many yilan, be they real or faking, will play into these beliefs, especially to avoid being touched by their public. False yilan will often perform a much more sultry and seductive dance, but will not want hands laid upon them.
A real dance will often intimidate onlookers. The movements, while graceful, seem contorted for a human body to twist into, being reminiscent of a snake. Real yilan all have otherworldly eyes with which they will stare at their public without ever blinking during the entire performance. Fake yilan will either wear contact lenses or cover their faces with a mask to hide their lie.
Real yilan, as well as particularly talented fake ones, get spotted in their youth and will perform in royal courts and fancy venues. That is unless they are kidnapped and sold to barbarian warlords as an exotic addition to their harems. They command a high price and, as such, many people will never get to see one in their entire life. The dance is often made into a show with a pungi player, the traditional snake charming flute of the Auriels, in which the player and dancer will pretend to have a fight for dominance.
While yilan dancing is exclusively associated with the Auriels and it is believed that only Auriels can be born as a yilan, they do occur in other races as well. The dance is forbidden by Bantaks as it is linked with demonic possession due to the serpentine qualities of it. The Margraces view it as utterly debauched and lewd and such performances will be hidden in brothels or illicit clubs.
It is very popular amongst the snake-worshipping Danakis where most prolific yilan, real or fake, will often become dance teachers, further propagating the art. However, they do incorporate vastly different movements into their performance. Therefore a Danaki yilan dance won't look at all like an Auriel one.
Since most Auriels look down upon the other races, they would never consider them to be real yilan.