Girl Wearing Superhero Panties

• Female superheroes
The first known female superhero is writer-artist Fletcher Hanks's minor character Fantomah, an ageless, ancient Egyptian woman in the modern day who could transform into a skull-faced creature with superpowers to fight evil; she debuted in Fiction House's Jungle Comics #2 (February 1940), credited to the pseudonymous "Barclay Flagg".
Another seminal superheroine is Invisible Scarlet O'Neil, a non-costumed character who fought crime and wartime saboteurs using the superpower of invisibility; she debuted in the eponymous syndicated newspaper comic strip by Russell Stamm on June 3, 1940. A superpowered female antihero, the Black Widow — a costumed emissary of Satan who killed evildoers in order to send them to Hell — debuted in Mystic Comics #4 (August 1940), from Timely Comics, the 1940s predecessor of Marvel Comics.
Though non-superpowered, like the Phantom and Batman, the earliest female costumed crimefighters are The Woman in Red, introduced in Standard Comics' Thrilling Comics #2 (March 1940); Lady Luck, debuting in the Sunday-newspaper comic-book insert The Spirit Section June 2, 1940; the comedic character Red Tornado, debuting in All-American Comics #20 (November 1940); Miss Fury, debuting in the eponymous comic strip by female cartoonist Tarpé Mills on April 6, 1941; the Phantom Lady, introduced in Quality Comics Police Comics #1 (August 1941); and the Black Cat, introduced in Harvey Comics' Pocket Comics #1 (also August 1941). The superpowered Nelvana of the Northern Lights debuted in Canadian publisher Hillborough Studio's Triumph-Adventure Comics #1 (August 1941), and the superhumanly strong Miss Victory was introduced in Holyoke (comics) the same month. The character was later adopted by A.C. Comics.