SNSFW

So Not Safe For Work.

One step further than NSFW (Not Safe For Work).

Those pictures of that naked woman doing that animal is SNSFW

sNSFW

slightly Not Safe For Work, as opposed to SNSFW for So Not Safe For Work and NSFW, which fits in between.
The leading S should be lower case to distinguish it from the worse version!

I said the picture of the woman with the animal was SNSFW, not sNSFW!