You have a few pictures on the first page, you have some of nearly every update.
This variable happen when: Myriam intervened during update ch2.05 when she catch Marc jerking off at the home made porn; and in this update ch2.07 in the rare case of Myriam waking up in Marc's bedroom with a high Willpower stat.
This variables overlap the other of Marc, being on the "dom", "sub" or "trust" roads, whatever the case, when Myriam intervened, this road stop for now and bring back Marc on the "normal" one with a simple mother/son relationship.
There is four roads for Marc: "dom", happen in the laundry room if Myriam chose to be submissive; "sub", happen in the laundry room also if Myriam chose to be dominant; "trust", happen before the laundry room on the couch if Marc play the "it's just a dream card"; and "normal", happen if Myriam put back Marc in place in the laundry room and in a way if she intervened like I said on your first question (in fact they are still on their road, but put to "sleep" for now).
On update ch2.07, if Myriam return from the gala shitfaced, two things can happen: if Marc is on the "dom" or "trust" roads and Myriam hasn't intervened during ch2.05, he will bring Myriam to his bedroom; or if Marc is on the "normal", "sub" roads or either on "dom" or "trust" roads if she intervened, Marc will bring her to her bedroom, just coping a feel if he's on the "dom" road.
If Myriam chose to follow "good" characters, like William, she'll be able to get out of the hands of some more "bad" characters, but with a limit, each roads will have some threshold where Myriam can go back, or it will engage in some closed ending roads if she pursue past them.
No, this variable can happen if Marc is on the "trust" road, so the trait the most important will be Trust (and Lust in second).
As other plot lines, this ones may have some endings depending on the choices.
As I built my next update (meaning ch2.08), which will bring a close to chapter 2, you will have an occasion for a lesbian naughty scene with Lucy.