
Ok. It makes some kind of sense now. The ML experienced what I call "poor people kindness" and he wants to experience it again. MC bought him a more expensive snack even though he barely had any money to spend for himself. And he expected nothing in return. It was simply done out of the kindness of his heart. Something that a lot of poor people will do. We may not have much but we will gladly throw money away on a gift or to help someone in need because we know what it's like to go without.
Not saying more well-off don't do this. They absolutely do but it's more common to see it in poorer communities. We tend to share things and buy each other things to help one another get by.

Yeahhhhh, sexual kinks don't just go away, especially ones like his

It can be both. Sexual kinks are not just about sex. There are a bunch of kinks that have correlation with mental health and environmental causes.
And the uncomfortable truth is some sexual kinks can be dangerous and downright criminal. Some sexual kinks should never be explored and people who explore them deserve to be on the receiving end of Vlad Tepes' stakes.(he staked people through their buttholes)

Hmmm... execution wasn't quite right. The action scenes were drawn at all the wrong angles and way too closed in on the people, no scenery or background details to convey how, where, and when an action is taking place. Hwayoung freaking out was very very quick. There wasn't any room to grow the panic organically. He just went from 0 to 100 within seconds.
He's gonna fucking kill you one day...