Also, I’d like to clarify something so that people don’t get the wrong idea!
Most fanfics I’ve read make every member of the group (if it is about a certain group) a nice person and part of the good guys.
However, since most groups I write about have five+ members, I don’t really think that making every member a good guy would work. I typically write reader x one member stories, and therefore I only feel obliged to make that member a nice guy.
So that’s why some of the members of a group are bad guys in my fanfictions. Not because I think they’re bad, but because it’s fiction. I love every member in the groups I write about, I don’t want anybody to think I dislike certain members.