Iroha keeps dreaming of her little sister, Ui. Kyuubey questions if Ui is or was even a real person, wondering why anyone would bother erasing her. But let’s not forget: Kyuubey is a trickster and can’t be trusted! Iroha’s apparent wish was to cure Ui, a wish that might result in Ui being cured, but doesn’t preclude her from disappearing, both from Iroha’s physical world and her memory.
There’s a medical center in her dream that’s a real place in Kamihama, so she sets off in the off-chance Ui is still a patient there. Her bus ride is interrupted by a Witch, who charms all of the passengers and lures them into a Labyrinth. Iroha transforms and follows, but again she is outmatched, as is a red-haired magical girl Akino Kaede. Fortunately Kaede has friends in Togame Momoko and Minami Rena.
Momoko, ostensibly the Mama Bear of their Kamihama trio, offers to help Iroha find her sister. Iroha supports Momoko, but Rena is opposed to any activities that deviate from their mission to investigate and stop the Chain Witch.
Iroha inadvertently serves as the catalyst for a huge dust-up between Rena and Kaede that leads to the latter saying their friendship is over, and Momoko only makes things worse trying to smooth things over. It’s clear that it’s hard in any universe for magical girls to get along, let alone maintain amicable friendships.
The thing about Rena is, she can shift her form to someone else, making a search for her the next day difficult. Momoko and Kaede want reconciliation, and so does Rena, but she’s held back, be it from pride, shame, or regret.
That’s when the infamous “Chain Monster” arrives, fulfilling the urban legend about writing your name and the name of a friend on a certain staircase to formally end your friendship. Just two episodes in and things get dark in a hurry, as the most cheerful and innocent of the magical girls is swallowed up by chains and dragged into the staircase. Rena and Momoko can do nothing to stop it.
The question is, is the Chain Monster the same as the Chain Witch, is the staircase a Labyrinth? If so, perhaps they can go in, rescue Kaede, and defeat the witch in one stroke. Or maybe Kaede is gone, forever. You just don’t know with this show!