Basically, everything involving the girls' sexual experience has... internal experience. Some may start better at something than others, but they allget better the more you do it with them. Kitty can't deepthroat at the start, and every girl starts with low to negative pleasure with anal sex until you do it a few times (and even then it has to start with some pleasure). Even spanking during scenes is like that.
On that same area, girls are easier to convince to do something when already high on pleasure. And have a better chance of doing it from the start after the first time. For example, anal or doing things in public (even Emma).
Speaking of doing things in public, if you do it enough times in public the girl will become an exhibitionist.
Girls have friendship values that may affect if they would enjoy a threesome, but pleasure may also affect it. And they do not go both ways, a girl may enjoy being the second but if you change your focus to them then she may decide it is not something for her. It also affects if they let the other girl spend the night in their room, if you go to sleep there.
Jean herself has two settings, one for threesomes and another for actual friendships. So you can have a girl who she can have threesomes with easily, but still hates her guts.
Massages can make even the girls less into you horny. Seems like there are three levels, and if you reach the end in that session she will go by herself into something she would never have if you had asked.
But if she is not into you yet, the first action in the massage will be a negative one even if right where they feel the best.
