Also known as: ほむ
A sound effect associated with Akemi Homura from Mahou Shoujo Madoka Magica. A play off her name in a similar manner to Pokémon. Homura's nickname among Japanese fans is Homuhomu. This phrase was never used in the drama, though.
A certain phrase written with Madoka Runes appeared in the Episode 3 and made this Meme well known: "Watashi wa Homuhomu ha desu (I'm in the Homuhomu sect)."