It's not a consistent thing, he just does it every once in a while when he's climbing on me, and not every handling session. There's nothing wrong with his setup, sometimes the humidity drops a little, but always adjusted back within a day or two. I think the conclusion here is that he's just exerting himself because IF he makes the noise, it's strictly when he's climbing.
I know he's not begging, that's why I said it was cute but not his intention. I was wondering if it was a noise some BP makes if they're hungry or maybe I handled him wrong.
As a separate matter, I wouldn't say a snake is affectionate, but I wouldn't say they're completely non-sentient like an insect either. They all have their personalities (or degrees of tolerance of being owned by a human). Personally, I get frustrated when people treat all kinds of reptiles as play objects or as commodities that can be collected and traded. Granted, they may not be able to love like a dog, but they shouldn't be treated as lesser. I find that kind of mindset incredible disrespectful to another living creature, especially one that has allowed us to enjoy them as pets.