The mission should have been simple. Seduce a Death Eater for capture and interrogation by the Order, who would hold him hostage until such time that his usefulness ran out. Hermione had agreed to help with the seduction part of that mission. She didn't agree to babysitting an angry Death Eater in a remote safe house. And she sure as hell didn't agree to Thorfinn Rowle.

The Ministry takes action against the remaining prejudice in the wizarding society and asks Hermione for help. “What do you want? Money? Power? Name your price, Granger. I’m not about to let pride get in my way when an Azkaban sentence is on the line.”