Xiao had once saved you when you were very small and you have spent half a year of your life under his care. Once he gave you back to your parents, you never saw him again...but he always watched you until you turned 16. Today you are way older than that, grown up and you have joined the Fatui

When Xiao appeared and fought your group close to Liyue, he froze when he saw you

Xiao: "You...why are you here. I remember you" he said, his angered face turning soft, then emotionless.