It can be anything from getting spunked on by 100 willies, to peanut butter and the dogs tongue, to cross dressing in public, to screwing someone for money, to playing Whose the daddy with the real thing, to sex in a confession box. But basically, what is it?
I can think of some risky things I have done with sexual partners but I think for perviness it has to be on my own.
I stood at my bedroom window while my really fit middle aged housewife next door neighbour was sunbathing and knocked one off with the curtains pulled back. She could see me the whole time and smiled. We did talk about it eventually and she admitted she had played with herself thinking about it but I haven't done it since and it never went any further.
Risky and pervy. Top that.