acid burns
A wound caused by a character coming into contact with caustic acid.
An acid burn can be shown as a reddening of the skin (or red patches on the skin), bleaching (whitening) of the skin, blistering, patches of missing skin (and fur/feathers/hair), up to exposure of muscles, organs or bone, depending on the depth and severity of the wound.
Acid burns are often most seen in vore involving graphic digestion.