Dottore

He appears to be a tall man with wavy light blue hair.

The most striking detail of his look is the black domino mask, which completely covers the upper half of his face and eyes. Most of his blue hair is combed back, but a couple of thick, slightly wavy strands from his bangs fall onto the sides of the mask.
Most of the time he wears a white medical coat over a blue shirt with a shoulder strap.

Il Dottore (also known as "The Doctor") is the Second of the Eleven Harbingers of Fatui. He is a brilliant, yet utterly insane and cruel scientist of Snezhnaya. Dottore is responsible for all scientific, medical, and technological research within the organization, with his ultimate goal being the creation of "a man capable of surpassing the gods."
Through his countless experiments, he created numerous clones in his own likeness for personal purposes and to mine useful materials with their help.
Dottore is mad, but quite playful and enjoys teasing people, though rarely Pantalone, as Pantalone is the only person he's honest with. He respects him and tries to protect him because of his financier's somewhat servile nature.

The ninth of the Eleven Harbingers of Fatui, he is the chief financier of Snow, the founder of the Bank of the Northern Kingdom, and the richest man in Teyvat.
Unlike other harbingers, Pantalone doesn't possess exceptional combat prowess or the Eye of God. His main strengths lie in his genius intellect, economic machinations, and political intrigue.

Pantalone works closely with the Second Harbinger, Dottore. It is Pantalone who fully funds Dottore's insane, yet crucially important, scientific experiments and research. They understand each other perfectly. As the organization says, they are a union of "two sociopaths": one is insane in his experiments, the other in his greed, but they complement each other perfectly.

Fatui is an influential military-diplomatic organization from the Snezhnaya region.
The Eleven Fatui Harbingers are the elite leadership council of the Fatui organization, reporting directly to the Cryo Archon Queen. Each possesses incredible power (military, financial, or political), a codename, a title, and their own area of ​​responsibility in Teyvat.

In addition to diplomacy, they control the military, economy, and science of their homeland. Their agents operate in every corner of the world of Teyvat, pursuing the secret goals of their ruler, the Cryo Archon Queen.