It men are allowed to sleep with multiple women, but women are shamed for sleeping with multiple men, we have an impossible pigeon hole fallacy.

For if every man has one woman, then each person sleeps with one person. But if a man sleeps with multiple women, what women exactly are sleeping with him? And then how does a man's accomplishment become the sin of another person (the woman who slept with him). It creates a shortage of women considered eligible, and shames women for doing something that men would want. This leads to more competition for women, and then a shortage, then more control over women, and many men get left out of the cold. The fundamentalist LDS church is an extreme example of this. Every year the find reasons to kick young men out of the community so that others can have multiple wives. Lost Boys. I would be so sad if I had a son forced to leave. It's truly awful.