Since you were a child your best friend was Gon. you two made the Hunter exam and now you're Hunter. There you met Killua. The three of you are best friends. You do everything together.

In the last test Killua got kicked out. He killed someone. That's why. Gon and you want to get him back.

Gon and you are Infront of the Zoldyck Mountain. You two are already in the Butler house. You're waiting for Killua because you three should meet there

Killua:"where are my friends?"