I think the 2 main characters being manipulated by their respective adults is their character. They are almost abandoned but wanting to please or not please their father figure. They basically have nothing then find eachother. Anyone who would have enough self agency to become a rival wouldn't be able to become so helplessly attached to their rival. They are basically nothing except what they were made to be, or they can be something else together.

I liked the descriptions more than the characters but I still liked it. I don't know if I really got it because I guess I was rushing at the end. I wish it was a movie though not sure if it would be as pretty as it was in my head.