Two Brother Sister Ideas

[SataiRolePlayingGuy]

1. Wealthy Man Pays You Small Fortune to Seduce Your Brother

Your character is an ordinary teen girl (maybe 13-16), nothing particularly special about you, but one way or another a very wealthy man has chosen you for a personal project.  He has offered you a lot of money to seduce your older brother.  The idea being to do it without saying it, but to give him hints, both obvious and subtle that want him to screw you.  To keep doing it until he does so and to keep encouraging him to continue.  After you have him doing it with some regularity, you will take to a prearranged location where it will be secretly recorded, both as proof and something for the man to keep for his entertainment.

He was willing to pay several thousand dollars as a down payment as soon as you agreed, with a promise to pay much more once he had proof it was successful.  He gave you the freedom to do the seduction however you wished, as long as you did not come out and plainly say what you were trying to do or why.  The rest of the money would not be given, if the brother knew about it before it was given.  Also with the end result, that the brother was expected to initiate the sex.

That is the basic idea, incest through bribery, neither one of them wanting it at the start but with the brother craving it by the end and the girl either remaining in it for the money and possibly getting more into as it goes on.  She has almost complete freedom in how to do it.  I would play as the brother, a year or two older than his sister.

2. Fucking Your Genderbent Brother Turned Sister

In this one I would be playing the girl.  For reasons that may or may not be relevant or covered in story, one of a pair of brothers finds himself turned into a girl.  It naturally turned life in the house around.  Their mother had to help her adjust to becoming a girl, and they were still in the process of updating all her records and convincing skeptical officials that one of their children truly changed from son to daughter.

The parents were caught up with this part of the process.  Their other child had different things to adjust to.  It was hard for him to see her as his former brother, instead he just saw her as a girl.  An attractive one as well.  While there was a degree of similar appearance, the new body was different enough that nothing about her appearance diminished his lust.  He tried to ignore it but eventually, but sooner or later, he decides he has to have her, and it did not matter that she was his 'new' sister.

This one is likely to more dubcon/bordering noncon early on.  While he might try a gentler approach at first, her rejection of such would lead him to desperation.  After the line is crossed, she might or might not gradually warm up to the idea.