Well not done... given how the choice at the end of the Molly route went. Not to mention that they are about to have their Holiday break from College, stuff might happen when Tales, Nikki and Molly are all under the same roof.
As far as the boyfriend, that's entirely dependent on the choice made at the party. I have two play throughs for that, if you don't want her to be with the guy, she'll still be single in this update because Tales convinces her that Marc isn't right for her.
I don't want her to be a LI, that ship has sailed, I just want her to be a continued fuck buddy for him and Molly. Molly is one lesbian encounter with Nikki away from that being a possibility for their future. Honestly if the twins planned it together, it could easily be made possible.
The one thing I just don't like is that this story seems to be steering toward the twins separating entirely at the end of it (like Nikki failing out of school or something). Even if without the sex between them, the two of them have clearly become much better friends and siblings over the course of the semester, it would be just a complete shame for the ending to be "Tales and Molly stay together, Nikki fucks off".
If the happy ending of this game isn't that the two of them remain in each other's lives, then the story development here would have all been a waste.