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After turning into a spirit by Phantom, Origami Tobiichi went back in time with the help of Kurumi Tokisaki in an attempt to fend off the Phantom who at the time she thinks was the Spirit who caused her parents deaths, which she was proven wrong just moments after she fended Phantom away, and the truth hit her very hard as she realized who killed her parents, Origami herself. As a result, she falls into extreme despair and Inversed, similar to but worse than what had happened to Tohka Yatagomi in volume 7. Upon returning from the past, Dark Origami started attacking the hospital and the surroundings where Shido and the other spirits are at. Shido Itsuka, bent on reverting Origami to her original self, approaches her, helped by Fraxinus to fend off her attacks.
However, thanks to Shido saving her parents while in the past, the world changed and moved to a different timeline. Here, Origami has long hair and a different personality as compared to her previous timeline self. However, her parents still died due to a car accident. She also was an ex-AST member, but this time her reason for joining and leaving was different.
However, this is not the end of the Devil Origami. Little did Origami know that she actually still manifests her Demon King, Satan, within her together with all her memories from the previous timeline.
Near the end of volume 11, Origami was invited by Shido to a date but turns into "Devil" upon seeing "Efreet" flames healing Shido's wound when he injured his left arm, while he tried to save her from falling off a cliff. With the help of the other spirits, Shido managed to reach Origami who was fighting over the control of her body with her previous timeline self. In the end, Origami finally succeeded in gaining control over her body and broke free of Satan's rampage, reverting into Metatron. Shido then took this chance to kiss Origami and sealed her power, ending Dark Origami's chaos.