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My coworker who is a black female, and I am a white male, constantly slaps me. The last incident took place as my boss an I walked in the door said she was startled and slapped me hard. She has done this on repeated occasions, and I have told her not to do that, but this time it left a welt. My supervisor asked if she heard us come in and she said she was concentrating on putting a plug in the wall.
She is in a management position as I am. She has been told before not to do that by other people in her area that have had the same problem. I am seriously close to going to HR about this, but I do not want to cause friction. I told my superior that the slapping is demeaning, embarrassing and uncalled for, but it keeps happening. I just do not like the physical violent action.