I was at the beach and met this girl and her friend, she had her friend cut me while she touched my junk.

I was at the beach with my gf, I had my dick out in the water and this girl came up to me and said "hi, I'm so sorry, but I'm gonna have to cut your penis." I was confused so she showed me a knife. Her friend came up and held me down for her. The girl cut me, I didn't feel any pain, just a weird tingling. I was really confused, I thought she was trying to steal my wallet, but then she started touching me. I was surprised, but then I felt her fingers. I wasn't sure what to do so I asked if she was gonna pay me. She said "no" and then left. I was in shock and went to the beach bar. The bartender asked me what was wrong, I explained and he called the police for me. I'm gonna be okay, no permanent damage. But what if she had been more aggressive? I'm glad nothing happened and I'm grateful for the bartender, but what the hell?