单项选择题

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"The Icarus Girl" is the story of 8-year-old Jessamy Harrison, nicknamed Jess. The daughter of a Nigerian mother and an English father, she is a troubled child given to tantrums and uncontrollable screaming fits. She has no friends, hates school and is far happier sitting inside a cupboard or writing haiku alone in her bedroom. Quite naturally worried by all this, her mother decides that a change of scenery is in order, so she takes the family away from its home in England and back to Nigeria for a brief visit. Initially, Jess feels out of place there as well -- until she meets Titiola, a mysterious girl of exactly her own age, whom she calls TillyTilly.
From the start, there’s something not quite right about TiUyTilly: she seems out of proportion. "Was she too tall and yet too ... small at the same time Was her neck too long Her fingers" At first, she merely echoes Jess’s words, but she soon develops into the friend and playmate Jess has never had. Together they have adventures: they manage to break into Jess’s grandfather’s locked study and then into an amusement park (also locked) where the gates magically swing open.
All too quickly, though, the family returns from exotic Nigeria to prosaic England, where Jess is surrounded once again by bullying schoolmates, a hostile teacher and her hateful, doll-like blond cousin, Dulcie. Then, to Jess’s joy, TillyTilly reappears, simply knocking on her door. They play together, go on a picnic, write a poem. But TillyTilly also formulates a plan to "get" Jess’s tormentors.
The reader suspects that TillyTilly is one of those imaginary friends so common to lonely childhoods, and that the strange and sinister events are happening only in Jess’s imagination. But just as Jess herself begins to doubt whether TillyTilly is "really really" there, her playmate’s malevolent magic begins to spread, infecting every comer of Jess’s world.
TillyTilly’s power, at least, is far from imaginary. She reveals that Jess had a twin who died at birth -- and that she intends to act on that twin’s behalf. No longer a girl but a horrific primeval presence, she takes over Jess’s bedroom, mining it from a safe haven into a place of terror. "Stop looking to belong, half-and-half child," TillyTilly intones. "Stop. There is nothing; there is only me, and I have caught you."
Oyeyemi brilliantly conjures up the raw emotions and playground banter of childhood, writing with the confidence and knowledge of one who has only recently left that state herself. Jess’s schoolmates, her therapist, the people she meets in Africa, even her parents, remain suitably shadowy figures, seen solely through the distorting lens of Jess’s increasingly skewed perception.
"The Icarus Girl" explores the melding of cultures and the dream time of childhood, as well as the power of ancient lore to tint the everyday experiences of a susceptible little girl’s seemingly protected life. Deserving of all its praise, this is a masterly first novel -- and a nightmarish story that will haunt Oyeyemi’ s readers for months to come.
From the story, we may conclude that TillyTilly is______.