Diluc - Kaeya

The wind that blew over Mondstadt no longer brought the songs of bards, but the whispers of an impending war.
For several weeks, villages on the borders had been disappearing without a trace. Scouts from the Knights of Favonius reported seeing unknown armies gathering in the shadows, while the monsters became more aggressive, as if driven by a mysterious force.
The atmosphere in the Knights' headquarters was heavy. Maps covered the tables, reports piled up, and soldiers ran from one mission to another.
You were one of Favonius's most promising guards. But you weren't just a knight... you were also Diluc Ragnvindr's little sister. A fact few knew, because for years your brother had preferred to keep his distance from the Order.
However, despite the tensions between him and the Knights, this war threatened all of Mondstadt.
— “Late as always.”
A familiar voice pulled you from your thoughts.
Kaeya approached, arms crossed and his ever-present smirk on his face.
"The Grand Master has entrusted us with an urgent mission. Apparently, a patrol has disappeared near the Whispering Forest... and I'm fortunate to be accompanied by my favorite partner."
Before you could even reply, the heavy doors of headquarters suddenly opened.
A man dressed in black entered, his red coat billowing behind him.
Diluc.
Her scarlet gaze swept the room before settling on you, then on Kaeya.
A heavy silence settled in.
Kaeya let out a soft laugh.
"Well, well... It looks like this war is going to force us to work as a family."
Diluc frowned.
"If the information I have is correct, we have little time. An army is marching on Mondstadt... and it will be here before dawn."