I enjoy the futa_is_always_bigger tag from Gelbooru. Thusly, I will make the effort to go through and tag as many relevant pictures as I care to as futa_is_bigger. I find that it may appeal to a niche (or sub-fetish) of futanari admirers.
penis_envy sounds okay enough, but to fit with breast_envy, it should only contain instances with people demonstrating envy, not just any size differences. (Not that breast_envy is the cleanest tag in the world, but hey.)
I find myself even more so fond of a penis_difference tag, as it appeals to a fetish of mine. Thusly I think it'd be at least as so useful. I will acknowledge that my initial idea was not thoroughly thought out, ergo coming to the forums.
To any accord, penis_difference does seem a bit vague, perhaps, seeing as how most penises are of a different size, to some degree. I'm merely caught up in the wording, is all.
My ideas for this tag.
This tag should describe a primary theme and fetish of penis size difference. A variant to consider is penis_envy, as something along the lines of penis_size_difference is essentially any combination of small_penis, large_penis, huge_penis, &c.
To break it down to its most elementary form, penis_size might be the most appropriate tag, as it leaves ambiguity to deal with the sub-fetishes of size-queens, humiliation enthusiasts, &c., whereas the satisfaction is derived from some sort of implication of penis size being of the theme.
john-x-hilbaerth said: describe a primary theme and fetish of penis size difference
Sound perfectly good for a pool.
I don't mind if you go either way, but for a theme collection being a pool will make it more popular. Users tend to actively add posts to pool rather than tagging so it'll help your idea grow in a long run.
If you do make it a tag, make it as narrow in scope as possible. penis size difference for the concept, leaving out whether any of the characters in the image are male or futa.
To supplement, create a "Futa Is Bigger" pool for those times when the bigger one is the futanarikko, specifically. That way, any futa on male pics where the futanarikko looks to have the smaller equipment would still show up in a penis_size_difference futanari search, and the pool would be there for those who only want to see the futa being larger.
sgcdonmai said: Well, we do have size difference and height difference; I'd say that's something like a precedent. If you do make it a tag, make it as narrow in scope as possible. penis size difference for the concept, leaving out whether any of the characters in the image are male or futa.
To supplement, create a "Futa Is Bigger" pool for those times when the bigger one is the futanarikko, specifically.