Lost memory of skin - Russell Banks

Suspended in a strangely modern-day version of limbo, a young man must create a life for himself in the wake of incarceration. Known only as the Kid, and on probation after doing time for a liaison with an underage girl, he is shackled to a GPS monitoring device and forbidden to live within 2,500 feet of anywhere children might gather. With nowhere else to go, the Kid takes up residence in a makeshift encampment with other convicted sex offenders.
Barely beyond childhood himself, the Kid is in many ways an innocent, trapped by impulses and foolish choices. Enter the Professor, a man who has built his own life on secrets and lies. A university sociologist of enormous size and intellect, he finds in the Kid the perfect subject for his research on homelessness and reoffending sex offenders. The two men forge a tentative partnership. But when the Professor's past resurfaces and threatens to destroy his carefully constructed world, the balance in the two men's relationship shifts.
Suddenly, the Kid must reconsider everything he has come to believe, and choose what course of action to take when faced with a new kind of moral decision.