A Hat Full of Sky

Tiffany Aching is going `into service': to be a lady, no less, a maid in a big house.But making friends with fellow witches is always difficult when an invisible-being-that-cannot-be-killed takes over your body - stealing money, and threatening violence. A Nac Mac Feegle of course - the rudest type of fairy, and handy to have in a tight spot .