A story concept I'll never have time to write
Beth and Carol were college roommates who discovered a shared interest in child porn and underage sex when they were freshmen.
It's 15-20 years later. In the meantime, each had a career and a family and an only child. The husbands share the underage sex secret, too. The families live far apart and only occasionally get together.
Beth's son Mark is 15. Carol's daughter is 14. Today the families are arriving at a remote mountain lodge they've rented for a week.
The kids don't know it, but they'll be sharing a bed with each other and rutting all week..
First, though, the parents must introduce them to each other sexually. Everyone will help as the teens are mated the first night with appropriate foreplay and coaching. Lots of oral. Inevitably, in my story, the girl would sit on the boy's face after he cums in her. It's just my way.
The week could include theme parties in the afternoons, such as gay, anal, incest and masturbation.
Anyway, if I could pay the bills writing porn, I'd write that one. Maybe it will launch a fantasy for you.
P.S. -- If you like visual porn and haven't discovered Tumblr, you're missing out on some amazing sights. My blog is stilleazinalong.tumblr.com, but you can go your own way when you get to the site.