House of Many Ways by Diana Wynne Jones

This book is the final volume in the much-loved Moving Castle trilogy. Set in the same enchanted world, each book has its own delicious flavour. House of Many Ways is an irresistible coming-of-age story, following the adventures of the unworldly Charmain Baker as she becomes embroiled in the magical mysteries surrounding the much-loved characters of Howl, Sophie and the fire-demon Calcifer.