Layla Rose Miller, also known as Butterfly, is a fictional character appearing in American comic books published by Marvel Comics. She first appeared in House of M #4, and was created by Brian Michael Bendis and Olivier Coipel. Peter David has developed the character, placing Layla at the center of the ensemble of mutant private detectives in his title X-Factor.

"House of M" is a 2005 comic book storyline published by Marvel Comics, consisting of an eight-issue comic book limited series with a number of crossover tie-in books written by Brian Michael Bendis and illustrated by Olivier Coipel. Its first issue appeared in June 2005 as a follow-up to the events of the Planet X and Avengers Disassembled storylines. The Scarlet Witch, her twin brother Quicksilver, and Magneto play major roles in the series. Like the Age of Apocalypse (1995–1996) storyline, House of M replaced the Earth-616 as the main reality for a brief time until Scarlet Witch reverted it to normal. The events of the storyline were later indicated to have occurred on Earth-58163.