Are you talking about the same game? 23 sisters right?
Spoiler warning!!!!!!!
The game where you have sex with and impregnate EVERY sister and some are underage? That's actually the f*ng MISSION you are on that is set by your father. At the point I stopped playing you were eagerly awaiting the birth and rapid growth of your own incest babies so you could F them and impregnate them too.
Had to go back and double-check. Yep, incest (meh) explicit sex scenes (good scenes) pregnancy (meh).