I think people are missing something when looking at this story.
Yuriko never stated she wanted to play the princess role and while she didn't stop Koro's weird habits she never forced her into it. Koro followed her and did things for her happily, and at the end was able to openly and comfortably express her own thoughts and opinions more because they had finally connected on less of a vertical power scale.
Yuriko by the looks of it was pissed being forced into a doll position, and I think the only reason why she accepted being called cute so much by Koro is because she realized how earnest and pure her feelings were. And while people may take offense to her constantly calling her a dog I think in her own way that was her way of showing affection, seeing as she really loved that stuffed animal.
The only real reason why I find this a bit off is because Yuriko and Koro never really stated their feelings clearly which is probably why you're looking at it as abusive.
I mean hey I'm not saying you guys have to listen to me, but I think it needs a deeper level of thought.