Maybe a plot where Dib discovers a new power within himself while chasing Zim across the stars. This power could be related to some sort of ancient alien energy that he has to learn to control. It could lead to an unexpected alliance between him and some of Zim's former foes who also want to stop Zim's crazy plans.
Dib is also very popular. His obsession with proving Zim is an alien and his determination, despite being constantly ridiculed, give him a lot of depth. Fanfiction often explores his relationship with his sister and his father in more detail, adding to his character.
Often, there's a theme of self - discovery. As Female Zim is a different take on the character, she might be on a journey to figure out who she is in this new form. Also, the theme of adaptation is common. Just like in the original where Zim has to adapt to Earth, Female Zim may have her own unique ways of adapting, whether it's to Earth's environment or to the reactions of the other characters around her. And there's also the theme of power. How does being female change Zim's perception and use of power? This is something that many fanfictions like to play with.
It depends on how you look at it. Some fans consider the comics canon because they continue and enrich the storylines from the show. However, others might have reservations based on personal interpretations.
Well, it's a bit hard to give an exact number. Different publishers and creators have come up with various Invader Zim comic offerings over the years. You might have to do some research to get a precise count.
It's about the zany and dark adventures of Invader Zim. Zim is an alien on a mission to conquer Earth, but his plans always go awry in the most hilarious ways. The graphic novel likely showcases his attempts, along with the equally strange characters he encounters, like Dib, who is always trying to expose Zim for what he really is.