If you're looking for a light hearted, by the numbers, hearts and flowers loves story this is not the book for you. It's complicated.
It's about an established couple looking for a third to help fill in the holes in their D/s relationship. It's destine to fail. At least, if they don't address the problems they currently have. Their chosen third brings even more unresolved issues and complications to an already difficult situation.
The Foster Family is a well thought out, nicely written story. Its an intense book. All the character's are flawed, imperfect, desperate to be accepted. At times this book left me more sad and dispirited. Characters asking each other why am I not enough? Will you eventually get tire of me and go for a newer model? Even though this book ends with a Happy Ending. Will it last? So I'm conflicted. I liked it, but I doubt I'll ever read it again.