There're also movies and games of HP, saying books is just a generalization.
Who the hell would do a 2D remake of a 3D game?! Their OWN 3D game! The clear thing here is FemU Zero has a different focus than FemU. FemU focused on the unlocking of femdom scenes, FemU Zero focuses on resource management. And right now, FemU has little to no story to it! FemU is more of a simulator, and a game with only the same setting, but with lore, different mechanics and downgrading 3D graphics to 2D sprites isn't a remake at all, it's just another game in the same universe.