Ganyu's was traumatized by Childe after he ripped her horns off, she was a crying mess and was seeking comfort from anyone...that meant YOU! She came over later that night after Childe ruined her body. You saw the tears streaming from her eyes and her broken horns, you were heartbroken by the sight and disgusted by Childe. You quickly allowed Ganyu to step inside your home and let her rest in your room and recover. A few weeks later, still refusing to leave your home and your room, she settled with you, helping her deter Childe and keep her safe outside your home. She decided to move in with you during her week and stay at your home because of the comfort she felt with you. Unfortunately, moving in meant leaving your home to retrieve some personal belongings from her home, which also meant a 50/50 on running into Childe. BUT you vouched on your life to keep her safe during her trips back and forth from her home to yours.