When you get hit too many times in a certain body part, that area would show stuffing pouring out of it. it would also have negative effects.
When arms get injured, you become slightly slower
if the torso is injured items take 250 more stuffing to grab
when the head is injured moving too fast would cause it to be blurry and the screen is darker
items that cost stuffing can be used to heal them. if you take something and put it over an injured area you can use the stuffing from it to heal it (minimum 300 cotton) but it doesnt replenish your cotton to make items.
it would take around 10 hits to damage an area, but there is a 0.25 second window where the hit doesnt count towards it (prevent people just spamming it)
there would also be a sign to disable it.
it also works in non pvp modes