We have competitive genes and cooperative genes. We are in between Bonobo and Chimpanzee.
There is a science behind who watches cuckold porn. Those who are "weak" or less competitive watches those porn. Some lesser weak people watch gangbang. Those who are in the strong side or "alpha male" side watch single couple porn, BDSM and anything that give possessiveness to them.

Pic related.
Thoughts. Is my statement wrong?