Hit Man by Lawrence Block

Keller is your basic Urban Lonely Guy. He makes a decent wage, lives in a nice apartment, works the crossword puzzle. Until the phone rings, and he flies halfway across the country…and kills somebody. It's a living, but is it a life?You've never met anyone like Keller.Keller is a killer. Professional, cool, confident, competent, reliable. The consummate pro. The hit man's hit man.But he is a complex person: understandably guarded and reclusive, icy and ruthlessly efficient, he is also prone to loneliness, self-doubt, and career worries. Keller may be a crack assassin, but he is also an all-too-human being.We first met Keller in Hit Man. He's back again in HIT LIST. Same job, new list of targets, and a hit man who's after him...

Meet Killer, the coldly efficient, yet decidedly human hit man. Your basic Urban Lonely Guy. He makes a decent wage, lives in a nice apartment. Until the phone rings and he gets on a plane and flies halfway across the country and kills somebody. It's a living. But is it a life? Keller's not sure. He goes to a shrink. He gets a dog, he gets a girlfriend. He gets along. There's no one like Keller.