I reallu feel puzzled by this cartoonist, Yoshihiro Togashi, I believe nobody can guess what he think in his brain. Thinking about the last manga he drawed called YuYu Hakusho, just have the same
way with Hunter. He use a special way to writhe a normal story, maybe its unormal, and he is actually a genius!
After talking with Kaito, Gon understand he have to become more strong to protect anyone he wnat abd also the weakness is not a fault, he hav eno need to feel appoligize to Kaito. Even though nobody told him that is Killua saved his life, Gon already know that. When meet with Killua, he just say thanks to Aluka and Killua. In order to comply his promise to Aluka, Killua decided to leave Gon and stay with Aluka and trip around the world. Actually thisis the unique way to protect Aluka and aviod his ability used by some devil guys such as Ellmi. So after say goodbye with Killua, Gon ready to remeet his father on the tallest tree in the mountain. Ging told his son about his definition and the top secret of this world, I think this will influence Gon a lot!
So Killua have the same destiny with Curarpika and Leorio, those two guys are used the main characters in the Hunter exam and Spider series. But after that, there are astart their own training and leave Gon and Killua together. And now Gon become alone, whether one of Curarpika and Leorio will come back? We will see!