Holiday Only Incest (MxF)

[SataiRolePlayingGuy]

This is pretty flexible about who is involved, it is more about a story idea.  The idea of a world where incest is still usually taboo, but because of unusual cultural/religious beliefs, people are not only allowed but expected to perform incest on several specific days a year.  Generally expected to be with opposite sex family, but same sex would allowed in a family with no alternatives.  It is something everyone has to do, but then be expected to go back to normal after it is over, until the next time one of these holidays happens, probably with considerable mutual confusion/reluctance especially if it results in a child (which happens sometimes, it is not the actual goal, but people are expected to avoid any sort of birth control at these times).  Thought it would be fun to explore the mindset of people involved, before during and after.  Possibly looking at their experience over several such holidays.  Each such holiday is probably a several day experience, possibly with a few days before to prepare and a few days after to get back to normal.  Each family probably has some discretion on what age each member starts doing this, with the assumption it will start sometime in their teens though.

I could play either the boy or the girl, in a Brother/Sister, Father/Daughter, or Mother/Son pair.