Between the Devil and the Deep Blue Sea by April Genevieve Tucholke

Nothing much exciting rolls through Violet White’s sleepy, seaside town… until River West comes along. River rents the guest house behind Violet’s crumbling estate, and as eerie, grim things start to happen, Violet begins to wonder about the boy living in her backyard. Is River just a crooked-smiling liar with pretty eyes and a mysterious past? Or could he be something more?

Violet’s grandmother always warned her about the Devil, but she never said he could be a dark-haired boy who takes naps in the sun, who likes coffee, who kisses you in a cemetery… who makes you want to kiss back.

Violet’s already so knee-deep in love, she can’t see straight. And that’s just how River likes it.