How many routes are you guys doing for this game? The choices in CH6 seems like you'll have to choose one or the other (or neither).
I have three: a full Jaye run, a full Mallory run, and my main run (which seems destined to walk the line between Mallory's path and a sexless run). I don't care about most of the other girls enough to chase their content.
What kind of incest in this game? mom/son, bro/sis, dad/dau, or stepcest?
Technically there is no incest in this game.
That's only a technicality, though. This game is very much of the "I'm not touching you, I'm not touching you!!" mindset when it comes to incest. The main LI is *not* the MC's step-sister because their parents have died subsequent to getting married. It's also implied
she's *not* the MC's half-sister since she was born to a surrogate mother due to some underhanded scientific chicanery. The other LI is *not*
the MC's mother, she just happens
to share nearly an identical genome due to even more underhanded chicanery. The girl the MC has sex with in Chapter 2 is *not* related to him, they just both pretend she's his step-sister during the act. You can *not* sleep with a side-girl and her daughter at the same time, they just won't let you forget if you sleep with each of them separately. And, of course, the game goes to great lengths to remind you that you are committing *not* incest at pretty much every turn.
Basically, this game is the ultimate incest poser; never actually does it, but will not drop the subject.