Two of the notable points from Episode 15:
Right before she is about to change her 1st outfit, Monica says, "You're half my age. And she(Zarah) knew your Mom..."
Second point is more like a theory, where MC just walked into an entire photo shoot setup. A setup set for him by none other than Monica. A setup where Zarah kept on taking pictures of MC and Monica for "private collection". One of MC's dad's condition is for the MC to stay away from Monica. Failing to do so, he is fucked.
And after the Photo shoot, Monica all of a sudden has proof against MC in the form of "private collection". It means that Zarah is in on whatever Monica is doing or maybe she has been tricked by Monica into taking those pictures. If Zarah is in on it, she would be the Lower level villain type character while Monica would be The Most Cunning Seductive Witch of a Final Boss. If Zarah too, was tricked by Monica, I wouldn't know what to say about Zarah.
If Monica "The Witch" theory is true, all of sudden MC's dad was the good guy, who did his best to keep his son away from trouble. Wouldn't be shocked to see Katie and Jenna being part of this as well, under Monica's orders.
All in all, great writing again
CheekyGimp, makes me go mad with theories as always.