Most decent men would not engage in a lengthy, private conversation with a girl your age whom they do not personally know.
I know it may seem flattering that older guys and men would take such an interest in you, but 95% of the time, they do not genuinely care about you, and are just using you for their own twisted and selfish desires.
I really hope this is just a hypothetical scenario and not something you have done or would consider doing.
I'm 17 and am hardly a prudish old fuddy duddy, but the idea of men aged 18-60 exploiting a girl your age infuriates and sickens me, and if there was a way I could leap through my laptop and throttle every one of them, I would.
I very strongly discourage you and all other girls your age from even IM'ing or talking on a webcam with someone aged 18 or older.
You are one of my youngest and sweetest contacts, and I want you to have more self-respect and to protect yourself from predators. I mean if the 13 year old is naked and playing with herself for the man if you know what I mean...