Conversationbetweengods Stories

In the middle of rewriting the universe by expanding her Labyrinth and altering her nemesis, the Incubator, Homura is approached by a strange creature that could easily pass off as a Familiar, if it wasn't for the fact this panicking hybrid of a Legless Crow with Butterfly Wings would separate into two clouds of smoke (one black, the other white), and turn into two teenage girls. Who were they ? What did they want ? And most importantly, were they going to be a nuisance fighting against her plan ?