I wanted to do a piece of children playing and enjoying themselves, despite being in surroundings that are not nice and even a bit harmful. It's a bit reflective, when I was a kid I would play by ditches (not as filthy as this), and I still had fun. Yet at the same time, I think we sort of owe it to kids to make a better world for them to grow up in so that they have safe and clean places to play in.
Final art - Photoshop
Rough sketch, pencil on paper
Finish sketch, Manga/Clip studio
Color rough, Photoshop