Fun book.
There's a fair bit of swearing in it which makes it inappropriate for younger readers. It's probably consistent with the vocabularly of typical teenagers.
It's a story of social misfits and to some degree. It's an exploration of what's right and wrong.
No real sexual content but it's alluded to occasionally.
We listened to this with my teenage daughter and we all enjoyed the story and didn't feel uncomfortable listening to it together.