Cheating or incest idea

Hello. I am looking for some playful roleplay ideas. I'd love to hear some ideas you have and would am looking forward to some new ideas. Here are some ideas I like and would love to play with someone.

Incest: It's just a kiss
The idea is that a loving older brother peer pressures the little sister into "just kissing". After all, it's just kissing and kiss is fun. However he begins to enjoy himself so much that he decides that they should try some fondling and touching. Maybe after that, he decides that she should let him perform oral sex on her. This story could work with the sister asking the brother for just a kiss as well.


Cheating: The swinging couple.
The idea is that a couple decides that they want to try a threesome. Any combination of people is fine. Either a couple who wants to add another man or the couple wants to add another woman. One of the rules is that the spouse (male/female) cannot have sex with the new person (female/male) without the present of the other spouse and the absolutely can't have unprotected sex with them. This story could go a lot of ways.