Well, it could be a really wild and imaginative plot. Maybe Amethyst has some strange power or is under a spell that makes her uncontrollably hungry for the entire planet. It might be a story about the chaos that ensues as she starts consuming the planet bit by bit, and the other characters' attempts to stop her.
The main character is Amethyst. However, depending on how the fanfic is written, there could be some minor characters that are affected by Amethyst's actions. Maybe there are some small creatures on the planet who are trying to escape or fight back in their own ways. And then there are the core characters from the SU series who are involved in either preventing or dealing with the aftermath of Amethyst's planet - eating.
I don't know who the author of 'Amethyst Novel' is. There are so many novels out there, and without more context, it's difficult to determine the author.
Since I don't have more information on 'Amethyst Novel', it could be a fantasy novel where amethyst has some magical properties. Maybe the main character has an amethyst amulet that gives them special powers. It could also be a love story set in a place where amethyst is mined.
Garnet could be a great addition. Her wisdom and calm nature could provide some contrast to Steven and Amethyst's more impulsive personalities. She could also offer some valuable advice to them during their adventures.
Self - discovery is another common theme. Amethyst may learn more about her powers, her past, or her true self in the fanfic stories. This can involve her coming to terms with her flaws and learning to grow as a character.
I'm not sure specifically as there could be many different 'amethyst graphic novels'. It might be about a character named Amethyst, perhaps her adventures, relationships, or some sort of fantasy world she inhabits.
There's a fanfic called 'Amethyst and Peridot's Team - Up'. In this one, they work together to solve a mystery in their world. It shows their unique personalities very well. Amethyst is all about action and Peridot is the brainy one in the team. It's a really fun read.