I Shall Wear Midnight (Tiffany Aching book 4)

The fourth book in the Tiffany Aching series – five Discworld novels by master-storyteller Terry Pratchett.
Tiffany Aching is discovering it’s not easy being a witch . . .

People respect witches, but also fear them, and sometimes Tiffany Aching wishes that being a witch was more in-line with the having fun whizzing around on broomsticks that she’d imagined.

Then something evil awakens that stirs up all the old stories about nasty old witches, and suddenly Tiffany starts to think that even just wearing a pointy hat seems like a very bad idea . . .

Worse still, this ghost from the past is searching for one witch in particular. He’s hunting for Tiffany – and he’s found her . .