Summer in Orcus by T. Kingfisher (aka Ursula Vernon)

Summer in Orcus - T. Kingfisher

This is a wonderful, entertaining, beautifully written book about portals, adventures and some of the most original world building and characters I've come across (I've never come across migrating houses before or half the stuff this author comes up with). Summer in Orcus is a book for teenagers that can be read and enjoyed by adults.