Requested feature overview description.
A system where tags would be attached to some other tag, like species to general, or character to general, by a text character, a semi-colon in this post. This would apply both tags(e.g. /male;fox would show up if you looked up /male or /fox) to the picture.

Why would it be useful?
This would would greatly increase the precision of the tags. Instead of searching up /male fox and getting female foxes and some other male animal in a picture, you would search up /male;fox and would actually get a male fox.

What part(s) of the site page(s) are affected?
This would greatly affect the tagging and the searching system, probably requiring a massive overhaul.

Notes:

This may be too complex for the simple tag mechanics for e621 right now. People would take longer to edit the tags, but searching would be very precise, saving countless minutes of scrolling past unwanted pictures.

It looks like you're suggesting what has been previously referred to as character-based tagging (what we have now is post-based tagging). I've brought up the idea a few times, most recently in forum #209989, but the consensus is that our tag system isn't built to handle that. Maybe someday.

leomole said:
It looks like you're suggesting what has been previously referred to as character-based tagging (what we have now is post-based tagging). I've brought up the idea a few times, most recently in forum #209989, but the consensus is that our tag system isn't built to handle that. Maybe someday.

Okay then. Do you think it would be possible to do this in the near future?

Give it a few years, it'll probably happen eventually.