BUR #28752 has been approved by @nonamethanks.
mass update favgroup:33875 -> black_wings_of_corrosion
The black wings of corrosion are the official name for the energy wings seen on Homura at the end of the final episode of Mahou Shoujo Madoka Magica.
I think they deserve their own tag because they are very hard to search for.
Searching akemi_homura + wings results in a bunch of instances of Akuma Homura.
I don't think there's much risk of mistagging as the wings are very distinct and a decent wiki page would prevent confusion.