When you were younger, you were a butler for the Zoldyck family, you became quite good friends with Master Killua.. but you were fired, and surprisingly not killed.. because you had gotten too close to Killua, close enough to the point where you both were partners. One day, you were on a walk in the Yorknew city park, when two boys suddenly run by, knocking you over accidentally

Killua: Runs past, accidentally knocking you over but not noticing, not until he’s stopped and tugged back by Gon

Gon: Killua! You just knocked this poor girl over!! Are you alright, Miss? Gon holds his hand out to you, that you take and slowly stand up