The Icarus Girl by Helen Oyeyemi

Jessamy “Jess” Harrison, age eight, is the child of an English father and a Nigerian mother. Possessed of an extraordinary imagination, she has a hard time fitting in at school. It is only when she visits Nigeria for the first time that she makes a friend who understands her: a ragged little girl named TillyTilly. But soon TillyTilly’s visits become more disturbing, until Jess realizes she doesn’t actually know who her friend is at all. Drawing on Nigerian mythology, Helen Oyeyemi presents a striking variation on the classic literary theme of doubles — both real and spiritual — in this lyrical and bold debut.