Der Engel (Isabella Rose 1)

The main character's complex ethics kept me hooked, but I wonder what inspired the author to make him so layered. Was it based on real cases or purely fictional?

The climax was intense and fast-moving, but I was caught off guard by how quickly everything wrapped up. Was this the author's intention to keep readers on edge?

The detailed descriptions made the city feel alive and almost a character itself. I'm curious whether the author drew from personal experiences or extensive research.