Everyone in this thread needs to read
@magustg1 and
@SimplyBartz 's comments for clarity.
And Mangadex (like any other online reader) has children and teenagers in it. Thinking back to when I was 18/19, can't say I was any less of a hypocrite at times. You learn to think things through as you grow, and as it turns out a manga community isn't one of those places where you grow. Not often, at least.
EDIT:
Also, reading with the assumption that an author is providing a backstory explicitly to draw sympathy is, in my opinion (and it is just a point of view, nothing more) a bit narrow-minded. I also think that looking for a redeemable excuse in this kind of manga was a shortsighted mindset considering the more realistic theme.
And it's also funny how people overuse the word "cliche" and "generic" with their "it's been done" attitude yet their ability as a reader tends to fall into a pattern just as often. I apologize if I'm attacking anyone but it's gotten rather repetitive seeing people complain from manga to manga about writers' ability while also having zero sophistication as a reader. That's a bit of a double standard if you ask me.