When Does Killua Leave Gon?

Episode 147 (2011)

Does Killua leave Gon in the end?

Bisky told Killua that if he's unable to beat Shoot, he must leave Gon's side...and he lost. he tagged along for some time as Gon lost his Nen. But, Killua removed Illumi's needle that was the source of his evasive nature, because of which Bisky told him to leave Gon.

Does Killua betray Gon?

1 He Stalks Gon On His Date

But he's also changed a lot by this point, and his murderous tendencies are somewhat less defined. This act of betrayal of Gon's trust, since Gon doesn't know that Killua is following him and Palm, is creepy and also puts his friend in real danger of being hurt if he's caught.