7 Souls

Mary expected her seventeenth birthday to be a blowout to remember, courtesy of her best friends, fellow New York City prepsters Amy and Joon, and her doting boyfriend, Trick. Instead, the day starts badly and gets worse. After waking up in a mortifying place with a massive, unexplainable hangover, Mary soon discovers that nobody at school is even aware that it's her birthday. As evening approaches, paranoia sets in. Mary just can't shake the feeling that someone is out to get...
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Mary expected her seventeenth birthday to be a blowout to remember, courtesy of her best friends, fellow New York City prepsters Amy and Joon, and her doting boyfriend, Trick.
Instead, the day starts badly and gets worse. After waking up in a mortifying place with a massive, unexplainable hangover, Mary soon discovers that nobody at school is even aware that it's her birthday. As evening approaches, paranoia sets in. Mary just can't shake the feeling that someone is out to get her--and, as it turns out, she's right. Before the night is over, she's been killed in cold blood.
But murder is just the beginning of Mary's ordeal. Her soul gets trapped in a strange limbo, and she must relive the day of her death through the eyes of seven people--each of whom, she finds, had plenty of reasons to hate her. As Mary explores the mysteries of her world, discovering secrets that were hidden in plain sight while she was alive, she clings desperately to the hope that she can solve her own murder, change the past, and--just maybe--save her own life.
With its blend of suspense, horror, fantasy, and realism, 7 Souls is an adrenaline rush of a thriller.

"From the Hardcover edition."