The Anointed Fae - The Anointed Fae Series, #1

Eons ago, nine gods representing the elemental bloodlines split the realm in three, separating elements to ensure peace between the fae. But as the barriers between the realms start to falter and the elemental magic dwindles, students born into the most powerful families from the three realms are ripped out of their worlds to study their elemental magic together for the first time at the newly formed Trigon Academy of the Arcane Arts. In an epic fantasy coming-of-age tale filled with romance, the story follows Oriel, a social, superficially driven redhead from the Leukós realm, and Aries, a sullen, lonely water elemental from the Tenebrous realm, whose futures have already been chosen for them by their families.
After Trigon, Oriel is set to marry a power-hungry playboy from one of the most elite fire elemental families in Leukós, and Aries is expected to follow her family's powerful, dark, legacy, despite being unaware of what awaits her. Though the two girls are vastly different, together they discover an ancient legend that not only forces them to lie but creates rippling consequences. Oriel and Aries realize not everything is as it seems, finding themselves working together to uncover the mysteries behind the legend, and unearthing more secrets than they could have imagined.