ok. ill try to give you all the hints:
rachel see you naked, hit the Door. Be gentile in the dinning room. (I forgot the name) later that ebony girl see you naked, later talk with rachel ask about that ebony sexy girl, only one response. later, talk about her.
... later...
in the night, you got mail from ebony sexy girl, erase it... but... the temptation wins, and see the pics... you starting "manual time", rachel will see you in action. then, you notice and continúe with your hand. rachel like it.
another day, talk with her in their room and invite her to the cinema. in the movie, she asking about the movie: say exciting and you will try with her.
in the night, you may see their naked chest and sleep with her, left your hand on her chest. in the morning, touch her leg and keep it there. she will happy.
ok, every time you say yes to her and if she looks you with gina... (work your relación with gina) you run for rachel.
she will found you in you room, one day latef
be patience and she want asking you something. say: relationship with her and gina. and bingo! you get sisterly lust!
sorry, bro. I forgot things, but this works.