IDK this is just what I got from the story
so basically what I think what happened was that when John ( the murder sketch dude who was sent to the gallows) went to the church as an orphan he developed a relationship with the now father(idk his name sorry) and I guess something happened that's not really clear yet that separated them and now there at this point. There's other things like the father giving John heroin when he was a kid which I think influenced him into his not normal behavior like hitting that cat.
no I believe that since peter offers kids of the orphan to make money, and the scenes with the little john sitting on bed telling him " there's two ways to stop pain, kill yourself, or go mad" that makes me believe that Peter offered him to some pedophile, and I think the heroin he injected him was to reduce the pain for him in bed.

Can someone explain to me what's going on? Sorry my brain can't keep up