A girlfriend guarding fetish (also known as a wife guarding fetish) is a fetish tradcon men have wherein they wank over not allowing their girlfriend to have sexual liaisons with other men in private. Girlfriend guarding fetishists tend to use the word 'cuck' as an insult, as well as other anti-male language.
Why people have this fetish
It's generally born from selfishness, sexual sadism, social sadism, possesiveness, rape fetishizing, sexual insecurity, and jealousy.
False political pretensions of girlfriend guarding fetishists
Girlfriend guarding fetishists often insist their girlfriend guarding fetish is actually an elaborate political stance to prevent the collapse of Western Civilization. Calling everyone who they regard as enemies as, "cucks", despite the fact that girlfriend guarding fetishists are probably the only ones spending hours looking at porn categories.
First of all, there is no evidence that female swinging within monogamous relationships causes instability, only counter-evidence. *Only* polygyny is associated with violence and harems, not polyandry or partner sharing within monogamous relationships.
Polyandrous societies are actually quite peaceful, such as in a few areas of ancient and modern Tibet, And as far as girlfriend swapping in monogamous relationships, one study has shown that actually strengthens monogamy rather than weakens it.
Girlfriend guarding fetishists tend to call people who don't have a sadistic fetish for girlfriend guarding, as cucks, which is in reference to a porn genre they are familiar with and a traditionalist insult.