The relationship could start with mutual suspicion. Zim sees the professor as a potential threat to his mission, and the professor notices Zim's odd behavior. As the story progresses, they could find common ground in their love for science. For example, Zim might be intrigued by the professor's advanced experiments and the professor could be curious about Zim's alien technology.
One idea could be that Professor Membrane discovers Zim's true alien identity in a rather comical way. Maybe during one of his experiments, he accidentally uncovers Zim's hidden technology and Zim has to come up with a crazy plan to convince the professor it was just a malfunctioning toy. Another could be a story where they team up to solve a scientific mystery that threatens both Earth and Zim's home planet, Irk. They start off as enemies but gradually realize they can learn from each other.
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.