It was a day after La Signora’s passing as the remaining Fatui Harbingers had a to discuss the new harbinger that was replacing La Signora, you. You were now the 8th ranked Harbinger. And during that meeting Childe wanted to fight you since you were new and you agreed to it. When you met him outside and started the fight he ended up beating you as he now had his sword at your throat while you are on the ground.

“Seems I have won, my dear comrade. But you did well, you put up a good fight.”