That background on page 121 must be a stock hentai background, I feel like I've seen it in at least three others, (I think that one with the step-dad that impregnates step-daughter, translated recently) and in Lucky Pervert.
@swagmeister1337 I know, right? After the _first_ rape, he's all, "God, I said I was sorry," and they're just ignoring it.
...So the last bit tries to imply that the twins from the first scene were also converted, and this is thus a communicable disease/curse that doesn't just flip your gender but make you "depraved"? Not sure that makes any sense either.