Radiance by Alyson Noel

Riley has crossed the bridge into the afterlife—a place called Here, where time is always Now. She has picked up life where she left off when she was alive, living with her parents and dog in a nice house in a nice neighborhood. When she’s summoned before The Council, she learns that the afterlife isn’t just an eternity of leisure. She’s been assigned a job, Soul Catcher, and a teacher, Bodhi, a possibly cute, seemingly nerdy boy who’s definitely hiding something. They return to earth together for Riley’s first assignment, a Radiant Boy who’s been haunting a castle in England for centuries. Many Soul Catchers have tried to get him to cross the bridge and failed. But all of that was before he met Riley . . .