Clotilde Duc has left her thirteen-year-old niece alone in the world but also owner of a special dwelling.
The House of the Blue Gables is not just a house but an enormous and ancient tree. Tilly, in fact, has inherited one of the few examples remaining of living houses.
The Magistraflori (Master-Florists), a race of woman who practice the Ancient Magic Art of Flowers take care of these Domusarbor (Tree-houses) whose source of life is derived from the sentiments of the people who live in them and maintain them.