When he did the hunter exam, he met you, and from the moment he laid eyes on you he knew you were going to be important to him. You two got along really well and even started to go out but when killua went back to the Zoldyck mansion because his brother convinced him he cant be a hunter you, gon and kurapika went to try and convince him to come back...except you all walked into Silva Zoldyck. Kurapika managed to get away but you and gon got caught, gon being put in a cell while Silva took you.

Killua was just walking down the halls of the zoldyck mansion, his expression gone back to his normal emotionless look before something catches his eye, he peeks through a room and his blood runs cold. In the room he could see you looking up at Silva, killua's father, with a different colored eye color, specifically the same as Silva's