Hot or not, she's sick in the noodle.
Tell her in plain terms that you did not agree to be her BF and that you want her to stop contacting you. Also send it to her in writing. Have a witness -preferably an adult -if you can, to both. Then document every time she contacts you. Time, what was said, everything. You may need it later. As for the guy, next time he calls, tell him that if he calls again you will lay a complaint with the police and they will trace his phone. *69 wont' do it but they can. Then if he calls again, do it.
You need to protect yourself from these psychos.And don't be afraid to get your parents involved.(Also, be a class act and don't redistribute the photos)
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A Parent, old geezer, and occasionally right. Good judgment comes from bad
experience, and a lot of that comes from bad judgment.