[icontrolyourworld]

Let's explore the topic of what is acceptable levels of "lewd". Please be advised I will be using terms that may be not safe for work. It would be fantastic if a mod could clarify these points so that there is as close to no level of ambiguity as possible.

Let's start with these 2 terms since devonin mentioned them:
Nudity/Nude/Naked
From Dictionary.com
naked or unclothed, as a person or the body.
without the usual coverings, furnishings, etc.; bare: a nude stretch of land laid waste by brush fires.
(of a photograph, painting, statue, etc.) being or prominently displaying a representation of the nude human figure.

Porn/Pornographic
From Dictionary.com
pornography; sexually explicit videos, photographs, writings, or the like, produced to elicit sexual arousal (often used attributively)
television shows, articles, photographs, etc., thought to cater to an excessive, irresistible desire for or interest in something

These terms straight from dictionary.com don't seem to convey explicitly the answers we are looking for.
I'm going to presume 5 main topics related to what may be considered under most societal norms unacceptable nudity: Boobs, Butts, Penis, Vagina, Body fluid. If there is a specific area that should be addressed that I miss, please explain.
There are a varying level of Nudity, this is the big grey area that needs to be addressed I feel.

Please attribute the following degree of nudity that is acceptable to the respective category of anatomy.
Varying degrees of nudity involved:
1) Completely covered by clothing, with no see through. This includes clothing designed to intentionally cover this specific part of the body. (if you don't include this as acceptable it would be assumed that any picture involving said anatomy/fluid is unacceptable even when fully clothed.)
2) Completely covered by tight clothing, but allows this specific area to be accentuated. An example could be tight underwear that you can clearly understand is the outline of a nipple or erect/flacid penis or outline of vagina.
3) Completely covered but can see through. Example would be a wet T-Shirt that you can clearly see nipples and areola. There's obviously the most grey area with this, if you select this option please explain how opaque this must be to be acceptable.
4) Exact coverage. Example would include a circular piece of tape that covers nipples, and only nipples.
5) Body paint. While it's not clothing, it's not necesarily naked.
6) Is exposed but Censored by a black bar
7) Is exposed but Censored by pixelation
8) Assuming the subject could be in frame of the picture; Completely exposed but blocked by environmental factors, such as a lens glare, plant, or other prop or accessory.
9) Completely exposed, and acceptable.
10) Please add your own comment here if neccesary.

Female boobs:
1) breast (including under, side, and in between but not including areola/nipples)
2) chest wall (in between boobs)
3) areola (any pink bit)
4) nipples

Female vagina:
1) Clitoral hood
2) Clitoris
3) labium minorum (synonym: labium minus)
4) Urethral opening
5) Vaginal opening
6) Perineum

Butts:
1) Gluteus (the fat part ya sit on)
1.5) Butt crack line (it's not really anatomy, similar to cleavage for boobs, it's just the area where a sharp division or a split occur, including this as it actually covers the next 2 in most cases)
2) External anal sphincter
3) Anus

Male Penis:
1) Scrotum
2) Shaft flaccid
3) Shaft erect
4) Glans
5) Perineum

Male chest:
1) breast (including under, side, and in between but not including areola/nipples)
2) chest wall
3) areola (any pink bit)
4) nipples

Bodily fluid:
1) Lactation
2) Urine
3) Semen
4) Saliva

A few questions:

If an image includes pubic hair, or is shaven but is the same area, what is the verdict on one or the other?

If neccesary, please explain how much area surrounding a specific bit of anatomy including to what degree of coverage including opacity should be included in the case that exact coverage is not enough.

Is a completely nude human figure (including anthropomorphic of course) that does not include detailed areola, nipples, vagina, penis, or body fluid acceptable? Examples include mannequins, and other artwork that depicts a naked human figure such as Adam from Nier Automata, or Ruto (from hyrule warriors or The Legend of Zelda Ocarina of Time).
Another example would be a not totally finished drawing that has the outline of a human form but not the details filled in for the "nude" anatomy.

That's all I have for Nudity, I think this is a good starting point. Onward to pornography!

I feel it is nearly impossible to fully address what constitutes pornography, for example this entire post if for some reason you derive some sort of arousal from; even though it's entirely text based, I suppose could be considered pornographic in nature, even though my intention is not to elicit an aroused state. Since pornoraphy can be derived from; to a massive extent by text, audio, video/picture, I doubt I could be the first person to accurately define what is pornography, use your best judgement. I'd say the following however is pornographic in nature, depictions of sexual intercourse, including vaginal, anal, or oral, or expulsion of bodily fluid from genitals, or the act of masturbation with intent to sustain arousal or climax. Some could probably argue very convincingly that that is not pornographic though, for example "it's art" and you have a whole mess. Good luck with this bit!

My opinion personally is you can have completely exposed human anatomy either by art or real life, and it's not pornographic in nature, for example classical arts, statues, or even modern depictions can easily be nude but not pornographic.
Creation of Adam (1512) by Michelangelo is nude but not pornographic
Most of Sakimichan's catalog of fantastic artwork in most cases includes nude but not sexually elicit/pornogphic material as well.

I do use my best judgement when it comes to this topic, as I too have an obsession with lewd materials (I also have an obsession for riding in the grey area of rules, as often times I like to gain an understanding of what a certain rule or definition really means). FFR is super reasonable I feel on the topic, but not the best for sharing explicit materials as there are rules against it, and for obvious reasons, not everyone here is 18+.