Now, you may feel like this may be weird or not at all lewd or graphic but the fact of watching someone do something sacred make them look vulnerable and thus it is erotic and in fact one of the most graphic and personal kind of fetish. Some porn couples or even in real life even have a contest on who will cum first and this adds spice to sex. An example would be a man jerking himself off either using hands or fleshlight in front of the woman who is fucking herself through her fingers or using a dildo/vibrator. But it may also be done without the two people physically touching each other-they may just opt to masturbate to the view of the other masturbating. Mutual masturbation may be done by two people helping the other cum through masturbating them. One of the spiciest porn fetish is mutual masturbation.
This is also about the fact that almost and majority of people actually masturbate-and the very though of knowing someone personal doing it to the thoughts of you is absolutely dirty. It is an ego boost and also incredibly arousing. Likewise, a man jerking off is also not an unpopular porn fetish-in fact a lot of women actually enjoy watching men jerk off especially knowing they are doing so to the thoughts of them. Cam girls often do this and this is a vastly consumed porn.
This is absolutely not uncommon for a lot of porn viewers as there a lot of porn clips of porn female ladies pleasuring themselves through a dildo or vibrator or even through their fingers. However the very act of masturbing or jerking off is also a fetish of a lot of people. When one masturbates he or she often watches the porn of his or her fetish, and it may be morally questionable hence this is often kept in secrecy. In real life, you often do it alone by yourself because it is an act of basically fucking yourself-it is supposed to be personal, something intimate to yourself. The very act of masturbation is not only and merely lewd in itself but is also almost a sacred act.