Ann O'Brien was created by writer/artist Art Adams, who conceived of Monkeyman & O'Brien as series that would enable him to draw monsters similar to the classic movie monsters that he enjoyed in his youth, like Godzilla, King Kong and the Universal Monsters [REF].
The character debuted in Dark Horse Presents #80 (December 1993) in a story titled "A Monkeyman & O'Brien Adventure: Tortorus".