A photo is deemed NSFW if it is:
Explicitly sexual in nature (suggestive) and includes real photos, cartoon drawings, and all styles of animations.
Overtly tasteless.
Slandering to any person or ethnicity
In addition to the above criteria, if a photo is a primary photo, it will be flagged as NSFW if it also contains a suggestive body part without the member’s face in the photo. If you have a borderline photo that is not considered NSFW and it was marked as such, there’s a chance someone who has ripped that photo is using it as a Primary Photo. Remember: The Bouncers will be MORE STRICT with those used as Primary Photos.
All illicit drugs
The almighty "F" word
A gun is ok but an animated gif or bitmap image of a gun being fired is NSFW.
Blood and guts..this includes real photos, cartoon drawings, and all styles of animations.
Simulated sex acts even with clothes on.