Guy Niava is an agent with Mossad.
We are told in a blurb for one of the adventures that "he is the man who makes bad guys disappear" which is pretty much exactly what his unofficial job description might be. Well, in the case of the three adventures that exist as of this writing, it would be more accurate to state that description will be, is, and was. Those three tales we follow Niava in are from three very different times in his life.
Our introduction to Niava comes when he is being hired by the very rich and quite beautiful woman Gabriella 'Gabi' Korman. He is recently out of the Israeli Special Forces and looking for work, largely to help pay for his upcoming wedding. Gabi, who will become a close friend and confidante, is looking for someone to teach her how to both survive and to take a fight to her enemy; said opponent having already killed her husband and teenaged son. Her battle will slowly become his. Interestingly, we are only given his first name in that adventure as the story is recounted from Gabi's viewpoint.
The second adventure takes place a few years later when Niava is very much a part of Mossad having joined after the death of this wife in a terrorist attack. His service is to help avenge the murder of her and others as well as help prevent such deaths in the future. While Niava had never openly asked or had it stated to him, he has always believed that it was through his friend Gabi that he became connected with that Israeli intelligence organization.
The third comes as Niava has spent enough years fighting very bad people and having to do some very unpleasant things to keep them from hurting others. He has tired of it and has decided to take a very long rest, if not a permanent one, on the farm of his brother and that man's family. Life, and yet another group of bad people, will not let his retirement last.