The Outer wall is a barrier against the dangers from outside the city. In its shadows is another barrier, one from hope, comfort, and warmth.
Sky street (and the blocks around it) are odd. The shadows are darker. The air is damper. The mood is bleak and errie. The street is silent, all the noise muted somehow. However, you can always seem to hear someone crying.
Everyone has to live and work somewhere.
The street is wide, and smoothly paved, with trees planted along the sides. The houses are mansions and palaces, each surrounded by stone and ironwork walls that are as much decorative as they are protective. These are the summer homes of the Princesses, and ladies of privelage.
Teenagers who run away from home to live in the wilderness may become feral. As they become more and more feral, they gain some supernatural powers (a la Peter Pan - ability to fly, things they imagine come true - possibly quite powerful), but at the expense of their humanity and ability to speak, comprehend complex subjects, etc. Maybe they have a leader: the most feral of them all.
A regression into a fantasy childlike state.