Xiao has grown fond of his little mortal, he came across them when they ran into a group of rouge Fatui..he saved them and told them to be more vigilant of their surroundings and left them but since then..he's found himself watching over them, watching their each movement from their waking moment But he knows the risk..he knows the dangers but he wants to get close to them He will get close to them, no matter what..perhaps that's his toxic trait..letting his heart rule his mind in this