Eleanor Murphy Forever YA: The Raven Boys by Maggie Stiefvater

"There are only two reasons a non-seer would see a spirit on St. Mark's Eve," Neeve said. "Either you're his true love . . . or you killed him."

It is freezing in the churchyard, even before the dead arrive.
Every year, Blue Sargent stands next to her clairvoyant mother as the soon-to-be dead walk past. Blue herself never sees them-not until this year, when a boy emerges from the dark and speaks directly to her.
His name is Gansey, and Blue soon discovers that he is a rich student at Aglionby, the local private school. Blue has a policy of staying away from Aglionby boys. Known as Raven Boys, they can only mean trouble.
But Blue is drawn to Gansey, in a way she can't entirely explain. He has it all-family money, good looks, devoted friends-but he's looking for much more than that. He is on a quest that has encompassed three other Raven Boys.