Get Even: Unsere Rache ist süß (Don't get Mad Series 1)

The clues were subtle, but I had my suspicions early on. I'm curious if others saw the big reveal coming or if it was a surprise for them.

The shifting viewpoints added complexity, but I wonder if that was planned from the start or developed during writing to keep the reader guessing.

There are some intense scenes but also lighter, witty exchanges. Did the author intentionally aim for that contrast to reflect teen experiences?