The tag implication #51950 sheath_cage -> chastity_cage has been approved.

Reason: I've explained a little bit about what is expected when using the tag sheath cage in the wiki page I've created and started tagging some existing art already. Basically, a chastity cage that are locking onto someone's sheath look notably different from cages that would lock onto a external humanoid penis (the locking mechanism may differ, the opening tip at the end of the cage lines up with the sheath underneath, the cage is protruding upwards and not concealing the balls like a downward curved chastity cage would, the way the cage would strain if the user is attempting to get an erection, where the pre/cum should dribble from, etc.)

Therefore I think it is relevant to create a separate tag to differentiate the cage designs for the two different main genital anatomy (humanoid vs. sheathed), like the tags already exist for humanoid penis vs. sheath (or animal penis). Simply combining the sheath tag with the chastity cage tag is not enough in most cases, as the sheath tag would be missing from submissions that have the whole sheath covered entirely with a dome-shaped cage. Which is fine, because it respects the 'tag what you see' rule, but it makes user searching for chastity device designs that are meant for canine genitalia struggle to find what they want to see (or not to see). If it is visibly apparent that it is concealing an animal sheath, it should be tagged as such.

Also I'm willing to continue through tagging the rest of the existing art in the database, but before doing so I've noticed all the derived chastity cage tags have the full "chastity_cage" suffix (ex. flat chastity cage). So before continuing with the tagging, should the tag name be change to 'sheath_chastity_cage' instead to be more consistent with the specific tagging system for chastity cages already in place?

EDIT: The tag implication sheath_cage -> chastity_cage (forum #377528) has been approved by @scaliespe.

So, I'm trying to understand the difference between a sheath_cage and regular chastity cage, but I'm not sure I fully get it. A chastity cage designed for a humanoid_penis is often curved (though notably, small "nub" cages don't have enough room to be curved) and points downwards and may be specifically shaped for a penis head at the tip.
post #1827735
But the way I see it, a sheath_cage usually points either nearly horizontally or upwards, lacks any curvature, and most certainly is not shaped for a penis head at the tip.
post #3949786 post #4005368
Is that right, or am I missing something? You mentioned some things I don't understand, like "the locking mechanism may differ" and "where the pre/cum should dribble from".

Chastity cages can be drawn with practically any kind of angle and curvature, so there's probably plenty of gray area on what counts as a sheath_cage. If my understanding is right, and we don't mind the potential vagueness in the definition, this implication should be fine.

Yes, it is essentially the idea. The way it protrude upward is the most apparent difference, lacking curvatures, and also the pointy penis tip that can poke out from the cage and suggest it is canine genitalia underneath would also be a deciding factor. If it's a cage with bars or side holes, it is also visibly apparent what type of genitalia is underneath most of the times.

The best way I can explain what I meant by 'the locking mechanism may differ' is with this example here:
post #1485369
The lock is placed below the cage and is locking the dome cage in place with an additional divider bar between the balls. This would only be an effective way of locking a cage if the character possess a sheath genitalia pointing upwards, because the conventional cage pointing downward would need to have the lock placed on top of the cage where it would connect to the ring. No humanoid cages IRL have the locking mechanism below the cage's tube as far as I know, because it wouldn't be effective. The way it locks is irrelevant though, as a lot of artists don't put visible locks on their cages anyway, it would stay a humanoid chastity cage or sheath cage regardless, but may give you more hints for tagging if it's present.

When there's a grey area like nub cages or flat cages where you can't tell what's locked underneath, I'm perfectly fine with keeping those established terms for defining that type of cage. flat chastity cage and nub chastity cage would remain as is with no additional sheath cage needed. Only when it is visibly protruding upwards or having a closer inspection of the design of the cage when unlocked to confirm it's a sheath cage would be tagged as such
Like here for instance:
post #3907280
Without the first 2 panels in this comic, this picture would not be tagged as sheath cage because it is not apparent what's underneath and it is pointing downwards. Most would assume the red penis tip is a humanoid penis tip and not tag it as such, and that would be fine.

'where the pre should be dribbling from'
post #3980205 humanoid
post #4167739 sheathed
When it might not be that clear where the chastity cage's end hole is because of resolution/artist style/bodily fluids, inspecting where the locked penis' fluid comes out of may help confirming if it's a sheath underneath or not.

w1479 said:
...

Ok, that makes sense. It seems like it sheath_cages should be identifiable. My initial gut instinct was that it feels a bit specific for a tag, but since slit_chastity (chastity_devices designed for genital_slits) is already a tag, I suppose having a tag for cages worn on/designed for sheaths makes sense too.

The tag implication sheath_cage -> chastity_cage (forum #377528) has been approved by @scaliespe.