edit: WAM here refers to https://en.wikipedia.org/wiki/Wet_and_messy_fetishism
The WAM tags all point to messy, which is then used to mean bodily fluids, which is mostly unrelated to WAM as a fetish. The "see also" part also mentions some WAM-related tags, which I can only guess related to an older meaning of that tag. The "dirty" tag seems to be its new replacement, but unfortunately the overwhelming majority of posts under that tag don't seem to be WAM related (a lot of "I haven't showered in a week" dirty, rather than "I fell into a vat of ooze" dirty).
The current structure of WAM tags can be contrasted with the foot tags: feet, foot_fetish, foot_focus, and foot_play are all different things, but all WAM-related terms are funnelled down into "messy", and even if it were corrected to point to "dirty" instead, it just means that the character is visually a little grubby, rather than dirty in a way that appeals to someone that enjoys WAM. It's the difference between the dry observation that a character has feet, and the observation that the picture is one that focuses on them or poses them in a way that appeals to people entertaining a foot fetish.
For example, if you're looking for WAM posts under that tag right now you might pick these out of the crowd:
- https://e621.net/posts/3202616?q=dirty
- https://e621.net/posts/3353445?q=dirty
- https://e621.net/posts/3262617?q=dirty
- or even https://e621.net/posts/3264239?q=dirty
But otherwise, unfortunately it looks like right now the "dirty" tag is as good a predictor of a post catering to a stinky-feet fetish as it is of a WAM fetish, even though it seems to have been intended as the hub tag for WAM content.
On a similar note, posts like this one have an element of both "dirty" and "mud", but I don't think it rises to the level of WAM fetish content at all. It's a nice pic for different more platonic reasons, but not scratching that precise itch, which means that even combining related tags isn't really a viable way to focus on this content. On the other extreme, things like slime don't seem to register as "dirty" to most people, so if you combine those tags then you really don't find much at all, let alone WAM content.
There are some tags out there like "wam" (somehow not aliased to wam_fetish) and "mud_covered", but their usage seems quite rare (both in the double-digits) and at least the first of the two seems like it's one otherwise reasonable decision away from being aliased up to wam_fetish and all the way up to messy and/or dirty.
At the risk of making this post more harebrained with another minor quibble: "dirty" isn't really a term I would associate with people looking for WAM content, or at least not in the same way that you know someone into bondage is going to type "bondage" in the search box. It feels similar to if someone had aliased "bondage" to a name like "detained" -- not necessarily wrong but too broad in some ways, too narrow in other ways, and not something you'd think of sitting at the search bar or tag box.
I don't know if there's an easy solution to all of this but I think unhooking wam_fetish from messy/dirty and maybe sending it to wam instead might be a workable option. (Ditto for all the other tags relating to wet_and_messy etc). I don't come here often so please take this with a grain of salt.
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