The Grim Adventures of Billy and Mandy does not feature any identifiable LGBTQ+ characters or themes. The narrative primarily focuses on dark humor, surrealism, and supernatural adventures, with no explicit or implicit exploration of queer identities or relationships within its storylines or character arcs.

The animated series "The Grim Adventures of Billy and Mandy" does not feature any identifiable transsexual characters or themes. Its narrative focuses on dark humor, supernatural adventures, and the misadventures of its main characters, without engaging with gender identity issues.

The movie does not contain any action or adventure elements.

The Grim Adventures of Billy & Mandy is an original animated series. Its characters, whether original creations or interpretations of mythological figures, establish their genders within the show's own canon, aligning with widely recognized portrayals where applicable. There are no instances of characters from a pre-existing source or prior installment being depicted with a different gender.

As an original animated series, "The Grim Adventures of Billy & Mandy" introduced its characters within its own continuity. There is no prior source material or historical record from which characters' races could have been canonically established and subsequently changed.