You are clearly making false assumptions.
Why was he at playgrounds in the first place? People walk their dogs all over, but he chose there.
Because it's impossible to avoid going near playground when I'm going for a walking with my dog. It's right next to the path.
He allowed her to come over repeatedly without the parent's knowledge. Whether or not they care where she is, he doesn't care that they know where she is.
Yes. I admit that this was maybe wrong decision. But you have to understand me. If her parents totally don't give a shit about her child, what would change if I told them or not. That's how I was thinking. But not for long. Later I decided to tell them. I was never trying to hide anything.
You can't undermine that relationship. You can offer assistance as much as possible, you can be good to the kids, but you will never be their parent.
Never? Why do you think that? You don't know that it is possible to adopt a child? You don't know that is possible to get children away of parents if they are not enough responsible?
He just kept allowing it to go further. He bathed her, he kissed her, he dressed her, he picked her up every day. I'm not saying he was doing these things for sexual gratification. I'm only saying that he needed this intimacy more than she did. He could just be a lonely guy who needed a purpose in life, but all of this was sprung from his own desires. He groomed her to this point, fostered the relationship, nurtured it, crossed many boundaries, and that is unacceptable.
And what's wrong with that? She is happy. And she makes me happy.
Only people who are hurt by this are people on the internet.