From what I have seen from others
Sis grab your tea cause it's a whole mess soo..
Later on in the story Mc find out that they aren't her "real" family I think they just adopted her and after she finds that out she starts to have sex with her brothers first and than if I remember correctly she starts to fuck her husband AND THAN her dad BUT it turns out that he already met MC before because MC somehow traveled back in time when the duke was young young like before he had his sons young and either he fell in love with her or they fell in love with each and somehow MC came back to present time and somehow lost her memories of when she and the duke were together but only he remembers and that's probably why he adopted her because MC looks like his lover (he doesn't know about the time travel only that he met a random woman) and the reason he treated her bad because although it's
I can't understand fl..she came from modern world and educated too..why she fucks the whole family ..he is not her biological father but still he raised her ??!!