Agent Diamond and Charming Guy are agents with an unnamed Canadian Intelligence agency.
At least I believe it is Canadian. Certainly there are numerous references to both operatives being Canadian and a couple of mentions of things indicating they are working in Canada but other than that there is a mystery. Adding to that, in the first recorded mission, they seem to be ordered about by the CIA (no mention of that Agency in the later adventures, though).
Another confusing issue is that when we meet them for the first time, they were both coincidentally in the same coffee shop and a bit surprised at that as they remark they had not seen each other for the past 10 years. And yet in the remaining few adventures, they are partners and work closely with each other. Another mystery.
Agent Diamond (and we never get any other name for her than that and that is how people call her) is described as a tallish woman in her early forties with a somewhat tired face and long brown hair. Diamond is definitely a woman of action who finds it easy to get bored unless she is in the thick of trouble and excitement.
Charming Guy (and again that name is all we are told and it, too, is used consistently by Diamond and others so ...) is said to be a tall and slender man with a ready smile. He has wide blue eyes is fond of wearing a fedora hat and likes to sport aviator sunglasses. He, too, loves adventure but does have more of an ability to take things as they come than Diamond does. Also interestingly, Charming Guy always has a satchel which contains an amazing amount of things, or as he describes it, "I have a knack for having what I need, exactly when I need it".
The sort of cases these two are sent on are whimsical although as we find in the first mission we have of them, we learn that getting hit with a ray that turns everything you are wearing - including undergarments - into orange pumpkin color does sound a bit serious.