Anything sexual with more than one person like HJs, BJs, fingering, pussy licking, etc, is most likely not going to happen, at least not with the triplets since they've only just met their Dad. Maybe we'll get an "accidental" kiss from Brooke on the lips and see one or the 2 of the girls semi-nude or fully nude like what happened with Allison before, and perhaps even see one of the girl's masturbate, but that'll probably be about it.
None of this is bad, however, as the slowburn of the relationships is sure to be a strongpoint as it will make it that much more satisfying. I imagine this game will be similar to DMD because that game also to spend time building good foundations with the estranged daughter to make her comfortable with the idea of being sexually active with her Dad.