Joe Haldeman 
All My Sins Remembered [EPUB ebook] 

Otto Mc Gavin is peaceful and idealistic by nature, an Anglo-Buddhist, who seeks employment with the Confederaci n because he believes in it and its mission to protect the rights of humans and nonhumans. The only problem is that the Confederaci n needs him as a Prime Operator for its secret service, the TBII, and the TBII wants Otto as a spy, a thief and an assassin.It’s not, of course, a problem for the Confederaci n, which simply uses immersion therapy and hypnosis for Otto’s training, and then sends him out in deep cover on a variety of dangerous missions on a number of bizarre worlds. But for Otto, it’s a different matter: what he has to witness and what he is forced to do take a terrible toll on him . . .