Horrid

"This is your curse until all is made right:
I'll have my revenge at the stroke of midnight.
For once the moonlight touches your skin ... I win."
Delta's family has been cursed. Every night, one of her sisters vanishes; and she's next. Desperate to save her family, Delta makes a deal with the very witch who cursed her. With only three days left to live, she has a terrible decision to make: Kill a target of the witch's choosing or lose her life ... and her soul.