My 21 year-old sister Sharon had her friend, Natalie, over (both former cheerleaders, my sister is dark haired, always tanned, very pretty, very flirty; Natalie is blonde, sexy, same personalty). I was working out on a heavy bag I had installed on the back porch of our farmhouse (fantasies of getting knocked out myself--stories of which I plan to tell.) I had been jumped by some guys at school, and was worried that they'd drive by the house and attack me. I felt a tap on my shoulder. Instinctively I turned and swung my right arm just as I realized that it was Natalie, wearing a very short white terrycloth robe. I connected with her jaw.
She just stood there for a moment, looking astonished, then dropped spread-eagle onto her back. She just lay there. Her robe had separated--revealing her nude body (she had just showered, was wearing nothing but her robe and had come out for some fresh air when she noticed me punching the bag). She lay there out cold for about two minutes before suddenly sitting up--(I must admit I found the sight incredibly erotic--and I did feel her up before fastening her robe). All she said when she woke up was, "Oh God!--You knocked me out, didn't you?"
I apologized profusely. After asking me how long she was out, she told me that she understood that it was an accident, stood up, said she felt a bit woozy but was OK.