These are all “puzzle stories” in the tradition of Isaac Asimov's early short stories. You'll enjoy them best if you just immerse yourself in the world the characters inhabit, get to know them, and then discover what is really going on, which may not be at all what it appears on the surface. By the nature of puzzle stories, almost anything I say about them would be a spoiler, so I'll refrain from getting into details other than asking, “What would it be like to know everything?”, which is the premise of the first story, stated on its first page.
Two of the three stories contain explicit sexual scenes and are not suitable for younger readers. This book was recommended (scroll down a few paragraphs) by Jerry Pournelle.