Hmm.
Well, I would say that i,Robot by Isaac Asimov (the actual book, not the film starting Will Smith) would make a pretty cool visual novel game.
In a nutshell, you would take the role of several different characters in the story (as the story shifts from different characters' perspective) as they interact with several different models of robots in the story. You would get choices as to how to interact and feel about the robots that you encounter and these interactions will effect the story and the overall ending you get.
For example, there is a part in the book where a robot has a dilemma about complementing a scientist's looks. As the Three Laws states, 1.) a robot cannot harm any humans, 2.) a robot must obey a human command, unless it conflicts with the first law, and 3.) a robot must defend itself from harm, unless it conflicts with the first two laws. Since being honest about the scientist's appearance can possibly hurt her feelings (emotional harm), the robot tries to avoid her, but since it is an order, it's difficult for it to refuse.
As the player, you can choose to speak to the robot and try to get it to understand the difference between intentional harm and honesty, in hopes that the robot will not commit suicide in order to avoid harming the scientist's feelings (Oh! Uh, spoiler alert!), or you can talk to the scientist in order phrase her words properly and eventually fix the issue for future models.
Basically, it's save one robot or sacrifice one in order to save thousands of other robots.