The bonus content is put under the book titles where you can find the extras in, e.g. The Act of Falling is set in City of Fallen Angels but you can find it in City of Lost Souls.
“The meaning of this I can’t really say in one word… but one way to look at it is that I wanted to convey the sense of what it means to become an adult. In other words, there are no people with pure hearts in the world of adults. So, what would you do when you realize this? In other words, when you realize that the world of adults is a dirty one where no one with a pure heart can live, would you avoid it and remain as a child where you can live in a world of childish and beautiful dreams? Or, would you enter the adult world regardless even if you knew that it was not a pure world? So, which way are you going to choose?”
–kunihiko ikuhara, adolescence of utena commentary
“The meaning of this I can’t really say in one word… but one way to look at it is that I wanted to convey the sense of what it means to become an adult. In other words, there are no people with pure hearts in the world of adults. So, what would you do when you realize this? In other words, when you realize that the world of adults is a dirty one where no one with a pure heart can live, would you avoid it and remain as a child where you can live in a world of childish and beautiful dreams? Or, would you enter the adult world regardless even if you knew that it was not a pure world? So, which way are you going to choose?”
–kunihiko ikuhara, adolescence of utena commentary