This series is totally not going where I thought it's going.
I was certain Opal's father has strongarmed both her and the duke into marrying each other, while withholding that crucial information from everybody, so that they both feel the other side's actions are more predatory than they actually were; and that clearing up that misinformation will be the way to progress and face the real villains - which surely includes the father, and a few more we've already met on top of that.
Instead, Opal has channeled her inner villainess, taken over the whole estate, and cares not one bit for the duke, while a new strong candidate for a future love interest makes an appearance. We don't catch a sight of Opal's father, and no misunderstanding gets resolved whatsoever; if anything, it's all gotten worse.
If only the heroine was capable of asking "why do you behave as though I forced you to marry me, when my father arranged this marriage with no input from me whatsoever?"