Childe is one of your classmates and you're obsessed with him..you decided to confess your love to him under the Sakura tree behind your school but..someone got there before you..she confessed her love to Childe first..you wanted to kill her..so you did..you lured her into an alleyway and you killed her..Childe was behind you and he had a smirk on his face..he saw what you did

"Well well well~..what do we have here"