It was a sci fi short novel, pocket size book, about 100 pages. I bought it back in the mid 80's, @ walgreen's.
There was this guy who I believe was an astronaut, human male from earth.
There was this woman who was an alien. She came from a planet that was mostly populated by women.
There were men on the alien planet, but very few of them. In fact, I think they had only 5 men in the whole planet. With men in such scarcity, the alien race was in danger of extinction. Ergo, the few men had the sacred duty of making as many babies as possible with as much of the population as possible, during their life time.
In the alien planet it was so rare for a woman to gave birth to a boy than when it happened, the woman was considered a queen for the rest of her life.
Our earth male astronaut found the alien woman. Can't remember the specifics, but they end up flying on a spaceship to the women planet (duhh).
Now the twist... the guy falls in love with the alien chic and decides that he wants to marry her and he wants to be faithful (meaning, doesn't want to shu shu with the rest of the women in dah planet).
Alien chic has problems understanding the concept because in her society, keeping a man for herself was "selfish", not to mention a danger for the survival of her race.
They arrive @ women planet, dude stays faithful to his alien chic, not sharing, and they have many babies, all boys.
Alien chic ends up with very high status in her society for giving birth to many many boys.
---- end of book ----
I've googled this for years to no avail.