A Guide for Young Wytches

I meet a dream boy on holiday, accept his invite to his dream mountaintop castle; but when I get here, it’s a nightmare of invisible staff (apart from old, sour-faced Lisa) and gardens of either freezing white snow or sheer darkness. Oh, and magpies who appear out of nowhere.
Now I’ve found a book for ‘young wytches’; but will it help me survive the castle, or is it just another trap?