I dont use disinfectant on the skin, but advise washing with soap and water after a session, same as you would if being flogged with horse hair.
I do wash the knives with an anti-bacterial soap before or after play. to ensure clean surfaces.
The marks you see are simple surface scratches, no more than what you get if you were to use a bic pen cap. Lite welts really.
If We want to contnue the knife play thread, perhaps a mod could help us start one.
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