Of course this means pregnancy is a must. My caveats is that the game doesn't go too much into the fantasy side of things, and I'm more amenable to sci-fi (genetics and body trans) influences. By realistic, it also implies that the setting itself shouldn't be too out of this world. A bonus would be able to see the offspring as actual, even if temporary characters rather than just a single image of a hidden babe in swaddling clothes or a female with a preg belly at the very end or at the epilogue of the game. Don't mind text games but obviously those that are image centered are better. All what I said are supplementary to the main need for a game with a modern day inspired breeding system. Seen Haramase simulator, free cities, lilith's throne, the hard way, CoC.