Follower A was inspired by the otome isekai shoujo subgenre, which largely revolve around having some sort of meta knowledge of the "plot" from reincarnation, time travel, or other means that may or may not be explained. Examples include My Next Life as a Villainess or Who Made Me a Princess.
Having some awareness of the genre helps given the play on common tropes in the story but is not necessary to enjoy this story.
Recent popular yuri examples of this genre include series like I Favor the Villainess or The Magical Revolution of the Reincarnated Princess and the Genius Young Lady, but Follower A plays more off of the shoujo ones, haha.