It's so strange to me when people argue that something can't work in a movie if audiences have no prior familiarity with it. That belief ignores the existence of entirely original movies, or original characters within those movies. Some movies and shows have characters who are fans of real comic book characters like Thor or the Silver Surfer. Other movies and shows have characters who are fans of imaginary works of fiction created for the films, like the way characters in Community
(I think that's the one) are fans of Inspector Spacetime
. It doesn't matter whether the character has a prior existence in real life, since all that matters is the role the character plays in the story.