On women they exist in two cases:
a)She succumed to peer pressure as women tend to do, and had some random unicorn or butterfly after a drunk night out with her friends.
These are the same "friends" that will tell her to cheat on her husband.
b) She has many tattoos and they are expression of her self mutilation. She most likely has a cluster B personality disorder.
This type of woman will most likely be promiscuous and a constant turmoil of emotions, looking to turn everything into a scandal. You will most likely be abused in the relationship, unless you're dark triad and beat her up when she starts with the abuse.
On men there are three cases of users:
a) Chads and dark triads: gangsters, those sitting long sentences, cartels, all use tattoos as a way to scare off their competition or show clan alegiance. Chad uses tattoos to borrow the dark triad halo(it works for him because no one will even think of outing Chad as a phony. Lookism means anything Chad does is positive and genuine).
b) Military/Navy/Tribal Warrior Culture:
this is the real origin of tattoos. These tattoos are usually easilly distinguised as expressing their unit. Their tattoos bear a certain weight and are usually respected and accepted(although it is common to regulars and NCOs. Officers were expected to uphold a certain degree of proffesionalsim and class, at least in the days before this modern clown world).
c)Normie males: normies are trying to borrow the dark triad/Chad association with tattoos in order to boost their SMV in a world infested with thug culture. Women easilly see trough this and in reality, tattoos do not increase their appeal. They often fail at even picking the tattoo and end up with video game characters, reddit jokes and brand loyalty logos.
The meme is propogated in the dude bro circles never the less and fuels a huge industry.