From the introduction:
In a world of seemingly endless negativity, there is one girl still holding out for a happy ending. In fact, she’s actively trying to create that happy ending with everything she’s got! Homura Akemi has gone through countless cycles of time to save her best friend Madoka Kaname, but she never succeeds. This failure will no doubt drive her mad in the end… but that is not the story of this Homura. For some strange reason, Homura’s ability to turn back time has started to insert her into stranger and stranger parallel worlds called Time Flows. These Time Flows can have relatively mundane differences from the original, like a world where everyone is oddly more spaced out, or could be ludicrously different, like a world that has a bar for the different Homuras of the multiverse! You enter into this odd multiverse just as the 38th most powerful Homura, Tamura, enters into the “Spaced-Out” Time Flow.