The character of Aku could be developed in a 'pregnant Aku in Samurai Jack fanfiction' by exploring how he interacts with the world around him differently. He may become more reclusive as he doesn't want others to see his 'weak' state. Or he could become more aggressive in trying to protect his pregnancy, which would be a new aspect of his character. Also, his relationship with his own power might change. Maybe he has to find new ways to use his magic that don't harm the unborn, which would force him to grow and adapt in ways he hasn't before.
One idea could be a crossover where Aku accidentally opens a portal to the Naruto universe. Naruto, being the curious and brave ninja he is, decides to explore Aku's world. They could start off as enemies, but gradually come to understand each other's motives and end up teaming up against a greater evil that threatens both of their worlds.
I'm not sure who Aku specifically is in this context. However, 'sexy bedtime stories' could potentially be fictional tales with elements of romance or allure, but without more context, it's hard to say exactly what they're about.
I'm not entirely sure as I haven't specifically played it. But generally, a visual novel often has a story with characters and different plotlines. It might involve themes related to the title, perhaps about female characters ('onna kanbu') in some sort of context, which could be related to a dark or 'aku no' (evil or bad) situation. However, without more information, it's hard to be more precise.
The unique plot. It likely has a story that stands out from others, perhaps with an unusual take on characters or a different kind of world - building.
No. Since they are described as'sexy', there must be some elements that are not appropriate for children or those who are not ready to be exposed to such adult - related content.
Since I don't have direct experience with it, it's difficult to say for sure. However, some visual novels have unique art styles that set them apart. Maybe 'aku no onna kanbu visual novel' has a distinct art style that enhances the mood of the 'aku no' (dark) theme and the portrayal of the female characters ('onna kanbu').