Implicating naizuri -> paizuri.

Reason: tit-fuck without tits

Disagree, they are two separate things.

The term "naizuri" plays off of "piazuri", doesn't it? Making it a subset?

Yes, but thats not the point.

Well, they're performing paizuri, but barely, due to lack of material. So, naizuri = laughable paizuri.

Technically speaking yes but if I were searching for paizuri I wouldn't want to see naizuri images, they should be separate.

Couldn't you just include and exclude flat_chest to differentiate the two, and not need a naizuri tag at all? Well, unless you want to be covered in the event of a flat chested person happening to be in the same picture as someone else performing paizuri...

By the same token, just search "paizuri -naizuri" or "paizuri -flat_chest". This is like saying "com_on_boy" should be seperate from the "cum_on_chest/stomach/pancreas" tags.

I don't think this is a good idea at all.

The whole point of naizuri is that paizuri is impossible without sufficient cleavage to squeeze a penis between. The two are somewhat related, but mutually exclusive.

If you want to be that technical, naizuri is more like a variant of frottage, since it involves rubbing the penis against a surface rather than any kind of enclosure or insertion of it.

*still is unable to see why a derivation doesn't logically call for association*
*well, OK, is able, but is naizuri weren't introduced, paizuri would still be in place, and even the flat chests involved can provide some enclosure, even if there's not a full wrap-around (as some regular paizuri pics undoubtedly exhibit)*

Because these are, in fact, completely different fetishes.