I hope there will be event when the D get accidental pregnancy from too much fking (and her clumsiness for no pill, late morning pill, or whatever you know her) then later her pregnant bulge shows and the story will somehow go on to the matured young mom version of D having a little baby son. Publicly, D told as raped.
And F as MC having family relationship with a player chosen girl to cover up the real incestous issue after D's pregnancy is known. Having another daughter with that chosen girl few months after D gave birth to a son. Later, that another daughter will develop a relationship with D's son.
Sequel (or Chapter XX): Fast forward 20 years, MC got road accident. Son replaces F as MC.
Let's begin mother(half sibling)-son and brother-sister relationship.
D will be in her late 30 as a MILF. And the sister will be around her 20, about the same as MC's age.