"Kick-Ass 3" never happened primarily due to a combination of factors, including the declining box office performance of the sequel, "Kick-Ass 2," which grossed significantly less than its predecessor. Additionally, creator Mark Millar indicated that he wanted to focus on other projects and that the comic series concluded with "Kick-Ass" and "Hit-Girl" storylines. While there was interest and discussions about a third film, ultimately, it did not materialize, and the franchise remains in a state of uncertainty.

"Kick-Ass" is a comic book series published by Marvel Comics, specifically under its imprint Icon Comics. Created by writer Mark Millar and artist John Romita Jr., the series was adapted into a film released in 2010. While it shares the superhero genre with Marvel and DC, its unique tone and themes set it apart from traditional superhero narratives. The film was directed by Matthew Vaughn and received a sequel, "Kick-Ass 2," in 2013.

"Kick-Ass" is rated R primarily for its graphic violence, strong language, and adult themes. The film features intense action sequences, including scenes of brutal combat and bloodshed, which contribute to its mature content. Additionally, it contains frequent use of profanity and explores themes such as vigilante justice, moral ambiguity, and the consequences of violence. These elements, combined with its dark humor, make it unsuitable for younger audiences, hence the R rating.