Personally I would just like to point out it is a GAME, I understand people get very upset and offended about things taking place in a fictional world, but really I do not fully grasp why it effects people in such a manner, it is all fiction after all, why do people care if there is morally wrong things in ADULT games. For example people have going mental over the rape topic in games, but why, that girl is not even real and everything that happens is a work of fiction, same applies to all topics in games. However I understand your concern regarding the appearance of some of the girls, I am not sure why you believe they look under 18 due to height and body maturity, to be fair there are many short girls out there with under developed breasts, and really the fact that the story teller has stated that the characters in question are 18 and over means exactly that and that will remain a fact where as your opinion will remain as such as well. and Simply put Patron is Heavily against any form of incest and that is the reason Patron has an issue with this game it has nothing to do with your above mentioned views of the characters within this story.
And let us be forward enough to admit that none of this girls look like 12yr olds, I really tried to see it and I simply can not, youngest I could make myself believe was 15, the fact they look more like 12 yr olds to you says more about you then the game developer.