He doesn't, and has already listed it on his main website (furry.science) that it won't be happening. Pasted from there:
All non-essential fetishes will be hidden behind a settings menu. If you see anything on this list that concerns you, don't worry; it will be optional.
Slightly dissapointing for me, but given how difficult it would likely be anyways and how controversial it is (there's already a thread up asking for vore, which is heavily split) it's not a surprise.
Probably a plug of some description that goes into the subject's nipple to prevent milk from lactation leaving the breasts, causing them to swell up from the excess liquids.
What level of functionality are we asking for here though? Something as simple as a penis-shaped embellishment to add near to the groin, or going as far as to have unique interactions (e.g. double penetration) with the dicks? And how much customisation will be possible? Will both have to be the same size, length, type, etc. or can we mix and match, like having a sheath containing a canid member hiding a slit with a horsecock below?
Try searching "Tatsu Dragon" then.
Big and very, very fluffy.
Or the ass, vag or cock. Would be okay for micro/macro, but I much prefer same size, might not be as difficult as I thought either, as bulging is a part of one of the top suggestions. If that was implemented, same size vore might not be too far off.
This is size difference though, the body parts are proportional.
As much as I enjoy vore, this sounds like something that would be extremely tough to implement.
Being able to use your own or the subject's cock as a sound would be cool as well, if the size difference is large enough.
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