Incest to beat all incest. Brother and sister have been getting it on between each other for years because they could not find anyone who could satisfy them better than the love they had for each other. The sister had been divorced because her husband wanted a younger girl, so the brother moves in with his sister who had three kids, since he was helping pay some of the bills anyway.
The Adventures of Emily Series Emily ("Hot Tub Service Girl") and her extended family take a trip while never leaving home. WARNING: Contains drug use! While the experience is totally positive and spiritually uplifting, those who have issues with this topic might look elsewhere.
A Story in the Brother & Sister Love Universe
I worked in radio for a month back in 1978. I finally get to use some knowledge from that month for one of my stories - About a brother who almost doesn't figure it out in time!
Two experienced juniors (twins Rick and Michael), plus a virgin (Terry), are picked to evaluate a prospective new teacher. Except the twins take Terry to a darkened room with a two way mirror that looks into the faculty john, right over the trough urinal. Where Terry watches the coach get a blowjob from the new teacher while the twins play with his nips and his dick and his hole, teaching him all the things about guy sex he never knew he wanted to know. And then things got interesting.