One of my favorite little moments in HxH is when Gon keeps getting smacked by Canary, and Leorio (and I think Kurapika, but prolly more so Leorio) was getting super pissed ready to fight at the 10th time Gon was knocked back on the ground, then Gon grabs Leo's arm and just looks him in the eye and shakes his head. I feel like at that moment Leorio (and Kura if he wasn't aware before) really starts to understand Gon to a deeper level.
I feel like Gon and Leorio (probably more so Gon) are such strongly characterized people that it's like you put them in a certain situation, and it's like dropping a boulder off a cliff. It ain't stoppin. But then you have this moment where Leorio realizes that him loosing control would really just undermind Gon's satisfaction in that scenario, and for the rest of time that Canary is smacking him around, they're calm. Because they know this is literally the best course of action to please their friend. And even though it's a fucked up situation that Gon is in, they know it'd be more fucked up and unfair in Gon's eyes that he'd have to live with a situation where they did get in the way. It's like if you can't handle Gon, get out of the kitchen.