When I first read this book I found it unrealistic and a bit appalling (you'll find out why when you read it). It's of the sci-fi genre, but highly unrealistic in some parts. I prefer believable sci-fi (Gibson), which some might argue takes the mickey out of the genre itself.
Ok, the protagonist in the book, Micheal Valentine is a result of a failed manned mission to Mars, where he was raised by Martians and then comes back to Earth not knowing anyhting about it's people, cultures and even women (sex!). Hence, the title. Even though he's supposed to be "alien," he steals the limelight as the most human person in the book, IMHO.
He starts to learn much under the guidance and protection of Jabal Harshaw, an author and his pretty little nurses who take Valentine under their wing. Valentine then forms a sort of 60's free love society where everyone sleeps with everyone, has the ritual of water sharing and become water brothers like they did on planet Mars.
Basically Valentine wants everyone to get along and live happily, which makes sense to him through these water brother rituals because, humans are in essence hedonists by nature. But of course like all other "Messiah" or special people, all good things have a vicious line drawn in between, as we are all pillaging little humans who want harmony but simply cannot stop our incessant need for conflict and chaos.
However, the author does slip some lovely gems into the book through his characters:
"If God hated flesh, why did He make so much of it? God is no sissy. He made the Grand Canyon and comets coursing through the sky and cyclones and stallions and earthquakes—can a God who can do all that turn around and practically wet His pants just because some little sheila leans over a mite and a man catches sight of a tit?"
"There was one field in which man was unsurpassed; he showed unlimited ingenuity in devising bigger and more efficient ways to kill off, enslave, harass, and in all ways make an unbearable nuisance of himself to himself."
"A desire not to butt into other people's business is eighty percent of all human wisdom."
So there you have dear readers, not it's up to you and whether you deicde you want to grok or not?
* I have the book if anyone wants to read, first person who wants it can comment here, and I will find a way of giving you the book, also please return it. It has special sentimental value :)