The unique art style is a standout feature. It combines detailed character designs with a distinct color palette that gives the story a particular mood.
I think there are several, but the exact number might change as new ones could be released. You might want to check reliable manga databases or official sources for the most accurate count.
In Madoka x Homura fanfiction, the power dynamics between them can be an interesting aspect. Madoka, as a very powerful magical girl, and Homura, with her time - looping abilities, have a unique relationship. Fanfiction could play with how they use their powers in relation to each other. Maybe in a fan - created scenario, they combine their powers to save a new threat that wasn't in the original series.
They are quite popular. They have a large fan base both within the manga - reading community and among fans of the 'puella magi madoka magica' franchise in general. The unique take on the magical girl genre attracted many readers.
One popular trope is the 'time - loop fix - it' where Homura uses her time - looping abilities to try and create a perfect situation for Madoka. This often involves Homura going through multiple loops, each time learning more about Madoka and how to protect her better.
Another theme is time - related. Since Homura has the ability to manipulate time in the show, many fanfictions play with this concept in relation to her relationship with Madoka. For example, stories might involve Homura going back in time to save Madoka in different ways or dealing with the consequences of her time - traveling on their relationship.