Medium_vore is before post_vore, i.e. you see the prey getting shoved into the pred's pussy, cock, nipple, asshole, or being swallowed in the mouth, without evidence of being soft_vore.
That way, people know that the prey is being swallowed whole with digestion from the pred without 'it' being hard vore, where the prey gets torn apart. There is nothing in between hard vore and soft vore, and talking with some role players (not on e621) it gets confusing of what is what.

This makes no sense.

Removed the tag as per our discussion on Discord.