Whether they are Stepsiblings or Cousins doesnt matter. But i would want them to not like each other in the Beginning. It changes however when at some occassione one of them sees the other naked. Unintentionally the Witness will have naughty fantasies….but at some point the sexual tension grows to much and they have sex. That would be the Point when both are kind to each other.
Anal sex would be part of it too and i thought that she would initiate the Request for it.
I leave it open for a potential threesome with her finding another Girl, because she gets interested in her for her attractivity. Possibly wants to explore bisexuality.
Source: reddit.com/r/eroticliterature/comments/fsxv7b/looking_for_stepbrothersister_or_cousin_incest
I’m actually working in one. It’s a super blended family with three step siblings (F/F/M) who are all bitter about being thrown together. I’ll let you know when it is done. It will be a day or two. I have several stories I’m writing at one time (after family goes to bed ?)
There is a book avaiable on amazon by Sandra Syn called Dirty Cousins that is along that line.