Round 2 for Season 1 Heartstopper

I ran into the Heartstopper Season 1 Episode 1 on the plane back to Taiwan, I do love it and finished both S1 and S2 in 3 days. 

It's my second round watching Heartstopper, love every line when Charlie talk to Nick.

I am always thinking why Charlie is warm like this, and what's make him became this guy. Don't know, and would like to know.