(This book has two protagonists, a male and a female, with no clear romantic storyline between them. If the female protagonist's promiscuity bothers you, you can drop the book immediately.)
This book includes the following:
1. A very classic opening with both parents dead, and a male protagonist who's a bit of a closeted smart-mouth, thinking more than he says.
2. A highly unconventional, widowed, motherly young woman with a nasty personality. Her traits include, but aren't limited to: a big appetite but extremely picky tastes, lecherous but choosy, greedy but an overspender, lazy but always looking for fun, quick-tempered and fond of acting superior, jealous but always making excuses for herself, and conceited yet idle.
3. A very wasteland-like apocalypse setting. Monsters like a tidal wave destroyed human civilization, and the survivors rebuild it in a world overrun by monsters, relying on a highway that can weaken them.
4. A very un-wasteland-like, comfortable life in a camper van. Other people having the pressures of daily life doesn't mean the protagonists do. At least on the road, they have plenty to eat and wear.
5. Monsters and anomalies with SCP elements, but not quite SCP, since monsters aren't the focus of this book.
6. A long road trip with road-movie elements, but not quite a road movie, since this isn't an episodic story.
If you ask me what kind of book this is, I can't answer. But if you ask what kind of story it is, I can tell you.
It's a story about growing up, and about finding yourself.