I don't know what the concept of the book is and what purpose it started with, but I will describe the story so you can understand my dissatisfaction. The sensitive romantic hedgehog, whom his friends kicked around like a ball because they think it's funny, don't want to hang out with him (as well as his real friends) because he himself was forced to change and become tougher so that everyone else wouldn't hurt him. This resulted in him being forced in the end to become the sensitive hedgehog again, the one his friends kick for fun, so that he wouldn't end up completely alone since everyone cut him off. What is the point then? If you are kind and sensitive, are you obliged, in order to have friends, to let others do whatever they want to you and upset you? Why shouldn't others make the effort to respect their friend's needs?