Yes, the MC is a first shown as a pedophile/creep, but he's shown to change for the better.
The anime a strong "slow burner", they practically spend the first few episodes just building his character and who he is, and his regrets.
He's not your typical "Cool Guy" or anything, he's a sad pathetic worthless individual at first, someone you hate, and that's because, the largest part of this anime, and to me, the most important factor that makes it unique, is the development and slow change you see over time with how the MC acts and behaves. His past actions will always haunt him, but he will learn to accept that and choose to be a better person.
He was chosen to be such a controversial character because it makes character development important, otherwise, it'd remain a neutral part of the story, something that lays in the back of your head, like "Oh, huh this dude really become more likeable over the past 2 seasons", instead you'll go "This dude is so fucking disgusting" to "Damn he's a badass"
If this kind of subject is something you still aren't comfortable with, or you don't care much for story, its your right to avoid it, but if you value strong character development and majority focus on telling a deep story, this is perfect for you.
