It's like a visible mark of corruption. It's often times put on relatively pure women, and slowly corrupts them into being super skanky or demonic or something like that

it's a womb symbol ,like a evil witch

Depends on the context. In mundane settings, it's either an indication that the woman is a slut, or in darker settings a mark of (sexual) enslavement. In magical settings, it's usually some form of spell or curse. Sometimes it's corruption, sometimes it increases arousal, sometimes it does something completely different. The only unifying thing is that it has something to do with sex.

see it ：

https://www.hexieshe.com/672594/

or

http://www.360doc.com/content/24/0712/12/27880450_1128582637.shtml

or

https://www.pinterest.com/pin/342344009195354322/

key：obscene tattoos；Succubus Mark；Succubus Tattoo

Appreciation of obscene tattoos, each of which represents a different meaning. After a special brainwashing and sacrificial ceremony, the pattern is tattooed on the lower abdomen.

I just searched for information online, of course I don't know too much, these things seem like some kind of ritual but are connected with pornography

Of course, overall, I personally think this is just an "adult sex toy" and these graphics are generally similar to "Love pattern".

Pure love and chastity.

Congratulations on the release of the noob version.

I will write an explanation of pubic tattoo.

The most likely explanation is that it started with the novel "The Fallen Princess Knight Jeanne" published in Japan in 2005.

The story is "A work that depicts the scene where a noble princess who fights with swords and magic to protect her country is violated by an ogre."

The following year, in 2006, it was published on the adult game board as "The Fallen Princess Knight Jeanne - A noble princess poured with an ogre's seed!"