2 Books Found

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"It’s set at a boarding school and the main character is named Evie (that’s her nickname at least) and it turns out she’s a descendant of a woman that lived there a long time ago. She falls in love with a kid named Sebastian and there’s some kind of magic she has. I remember one of the books in the series has a necklace on the cover. There are only two or three books in the series. She has either some kind of fire or water magic"