Recently I went through and cleaned up tail around penis for any that were not containing a tailjob or had a visible penis.
Something I noticed was a lot of images that were not of tail insertion, tail penetration, or had a visible and untagged penis (or dildo), were of a female getting their pussy rubbed by a tail.

Some examples:
post #1415195 post #4756159 post #4192123 post #3459449

This does not have a good tag for it. Rather it has several tags that are all underpopulated for the number of such images on the site.
tail_against_pussy , tail_on_pussy , tail_rubbing , tail_humping, there's likely 3 more I'm not aware of, at the least.
I'm not sure how to clean this all up, definitely a good portion of these should be aliased to something else, and some should implicate another. I however am unsure how to approch it all. So I ask for help in unifying this... concept.