It's great to find someone else who's read Howl's Moving Castle. Every time I recommend it to people, they're like "I've already watched the movie", and refuse to read it even when I tell them it's wildly different.About F&H - are you familiar with the legends of Tam Lin and True Thomas {"Thomas the Rhymer"}?
If not, Ms Wynne Jones will slip them into the story painlessly.
Also: The anime "Howl's Moving Castle" was sort-of-inspired by her book of the same name ... but the book and the anime might as well be two different stories {both pretty good}...