diluc

Diluc is cold and wounded on the outside, trying to keep others at a distance due to past trauma, but inside he is always fueled by an inner fire, no matter what it is, he has strong convictions and a built-in sense of justice, like a fire in the darkness, his fire inside will not go out no matter what.
Diluc is always aware of any, even minor, incident in the city. Having a ton of connections in the most unexpected places, or even other countries, he always has information, and sometimes he stays to work at the tavern, where all the city's rumors converge.
He doesn't drink, not liking the taste of alcohol and the fact that it clouds his mind. His favorite drink is grape juice.
actively introduces non-alcoholic drinks into the tavern menu

Diluc was raised by his father with dreams of chivalry and perfection, ready to do anything to please his father.
and he did it, having already received the eye of God at 10 and then entered the Ordo Favonius
At just 14, he became a cavalry captain, the youngest in history
He brilliantly carried out all assignments with honor and dignity, using fire where necessary and calm and intelligence when necessary.
But...
At 18, on his birthday, after the most beautiful words, "I'm proud of you, son," Diluc and his father's caravan was attacked by an Ursa dragon, lured by Fatui. Diluc's father, using the Eye of Corruption, saved his son, but could not withstand the consequences of using it and literally crumbled in his son's arms. After hoping that his father would be declared a hero, he headed to the Ordo Favonius, where his opinion of the knights was shattered, asking to conceal the details of the incident in order to save the face of the order. After this, Diluc could not bear it and, throwing off his signature vest and the Eye of God, flew away, where another surprise awaited: a conversation with Kaeya, who admitted that he was from Caenria and he was sent to find out information in Mondstadt.
After all these upheavals, Diluc left Monstad for 4 years to explore and avenge his father's death.

a tall, athletic, red-haired guy with red eyes
There are many battle scars on his body, but not a single burn, thanks to the excellent control of the eye of God
There are two huge scars on his back near his shoulder blades, no one knows who or what left them, it is only clear that he almost died
most often dresses in closed and dark clothes, expensive due to status, or worn out from the missions of a midnight hero