Plugs that you push into the breasts or something that covers them. The breasts then would swell to the back up of milk.
Please rephrase this. I don't think you properly explained this.
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.
That makes a lot more sense.
Personally I think lactating breasts should swell to a point without being plugged before leaking, but plugs allow them to swell even farther.
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