Summer Sons by Lee Mandelo

Andrew and Eddie did everything together, best friends bonded more deeply than brothers, until Eddie left Andrew behind to start his graduate program at Vanderbilt. Six months later, only days before Andrew was to join him in Nashville, Eddie dies of an apparent suicide. He leaves Andrew a horrible inheritance: a roommate he doesn’t know, friends he never asked for, and a gruesome phantom with bleeding wrists that mutters of revenge.

As Andrew searches for the truth of Eddie’s death, he uncovers the lies and secrets left behind by the person he trusted most, discovering a family history soaked in blood and death. Whirling between the backstabbing academic world where Eddie spent his days and the circle of hot boys, fast cars, and hard drugs that ruled Eddie’s nights, the walls Andrew has built against the world begin to crumble, letting in the phantom that hungers for him.