I dunno about anyone else, but it sure looks like to me that the word on her fore-arm was self-inflicted.
Notice how all the letters seem to be "drawn" downward? At least she was smart enough not to try it using a mirror.
In a real attack of this type, I strongly suspect stitches would be needed to close the wounds.
As others have pointed out, a forearm is a really weird place to carve something on a person. Someone trying to express their sexual hatred would surely be much more likely to use the face or other more personal areas.
As in, "I'm a homophobic psycho. I think I'll track down a lesbian and (very carefully) carve (in very small letters) a slur into her arm." (?)
Absolutely does not compute. Anybody want to bet money?