Just a random MLP TF thought in my head. Man visits Doctor's Office for a possible flu. Unknowingly its Discord, as first his nose is begins to form, with him feeling it shock. To make matters worse, his clothes are getting baggy, shrinking in size while Discord claps his hands.

I don't view it as Humiliation. I just feel with MLP, having a person shrinking in clothes, hitting some 'Oh this is fun' aspects of THE WITCHES/ROCK A' DOODLE. Where your robbed of size, but still the same person per se.

With this thing in my head, as the guy is shrinking, Discord would mention the growth of wings and/or unicorn horn; hearing the skull popping or the back doing such to force their growth.

Thought the biggest shock would be the hips giving a pop, forcing the man to fours.

While not painful, it would be like someone taking all the fingers and toes, taping them together, and then even more as the keratin hooves form. Discord would be petting the man, telling him that he is suffering a case of Metamorphosis.

I also like the concept of someone tugging on the ear. Not really tugging hard, but enough for the person to get annoyed over the concept of, 'Oh look, this isn't Human anymore, just like you.' and the person unable to swat at the hand but only stomp/clop.

Naturally there would be some elements of humiliation, as they would be too small for their clothes. Naked as Discord balls them up, saying something like, "I think this is a better look for you! Clothes are meant for Humans, not Ponies"

Just enforcing verbally of the changes.