For unknown reasons, Origami knew about Shido even before he met her, and she is determined to be Shido’s lover. Origami will use any chance she gets to make her relationship with Shido more intimate. Her love for him is quite unusual, making many blunt and direct ways of seduction, yet at the same time, following most of his requests with a high level of trust, and has shown deep signs of concern for him in her own way.
Origami is very foward to the point of pervasion with her attraction for Shido and tried seducing him with her actions, such as buying a new bed, making herself deliberately vulnerable, giving him a combination of strong energy drinks and preparing traps to entice him to her. Shido is normally shocked and speechless at her actions, however after Origami became a Spirit in Volume 10 and Shido was told to make her fall for him, he displayed complete awareness of her carnivorous nature and stated that he was worried that he'd be devoured by her instead.
Origami has also proven to value Shido's life greatly, even willing to fight the DEM, and going so far as to steal a dangerous CR-Unit from AST and combat them specifically to protect him, when they planned to capture him. However, her fight against the Spirits are a more complex matter; while Shido has tried to make Origami try to speak to Spirits in a peaceful way, Origami declined because the deaths of her parents were caused by the actions of a Spirit, and because of her mission as a member of the AST.
During Volume 11, it was revealed that the source of Origami's feelings for Shido were not romantic, but instead was a severely high level of emotional dependance because of a promise that Shido (having traveled back to the day of the fire 5 years ago, and having transformed to his 11 year old self) made to keep her from falling to despair at seeing her parents death (having been killed by her future self, when she traveled back in time to stop said event from occurring).
Shido said to the young Origami of that time that he would take all of her feelings of sadness, anger, and hatred, and that she can use him if she ever finds herself unable to do anything on her own that she can use him however she likes, and that she can even hit him as many times as she wants, as long as that will keep her from sinking into despair. These words cause young Origami to cry into his arms, and shedding her tears, proclaiming that she will leave all of her tears, smiles, and laughter to him, but, will keep all negative feelings like anger, and hatred towards the "Angel" that killed her parents, and tells him to keep her feelings until the day she kills the "Angel".
After transferring to Raizen High, the new Origami was stunned by the resemblance between the Shido of the present and the Shido that saved her parents (she was unaware that the two Shido's are one and the same). She then concluded that the present Shido was the other one's younger brother. Shido then arranged a meeting with the new Origami to discuss about her in the new timeline. They talked about how her parents died four years ago in a traffic accident, and the reasons why she joined the AST (being inspired by the past Shido's action of saving her parents and to protect people from the Spirits), but retired due to the frequent blackouts that she suffered recently.
Afterwards, Shido more or less asked her out on a date so they can talk more, which she agreed to despite being embarrassed. For the Origami of the new timeline, her feelings were complicated due to subconsciously inheriting the original Origami's memories after becoming a Spirit in the new timeline. This caused her to be attracted to not only Shido's looks, but also his smell and touch. Upon fully regaining the original Origami's memories, she told Shido that before she didn't truly love him and used him as a reliance. However, her real love for him had begun to blossom during their date. Origami has since grown to be truly in love with Shido, rather than just using him as a dependent. However, her unhealthy methods of flirting with him have not died down, and often resurface when the Old Timeline Origami takes control of her body.
Origami sees Tohka as an enemy, love rival, and an annoying "baka" that gets in her way with Shido. Origami shows little respect for her as the quarrel between them as Spirit and AST member remains unsettled despite the fact that Tohka's powers are sealed. Origami does not trust her very much as she views every other Spirit but is not hostile to her due to Tohka's currently sealed status.
Shido has noted that even though they are different in nearly every way possible, they also similar in many ways, mainly their shared stubborn nature, desire to protect Shido, and their strong jealously for any woman who try to seduce him.
In Volume 10, it is revealed that Origami actually began to get used to living with Tohka and the other spirits. Enraged by this, she decided to defeat Tohka and the other spirits once and for all and return her life to normal. During the battle, Origami was able to defeat Tohka, Miku, and the Yamai sisters in their limited release Astral Dress. However, just as Origami was about to finish them off, Tohka regained her full power and defeated her. This resulted in Origami accepting Metatron from Phantom in order to gain power.
After <Phantom> made Origami a spirit, she obtained many long-range abilities which made her a bad match-up for Tohka who mostly uses close-range abilities. During the battle between the two spirits, Tohka asked Origami if they could perhaps find a way to understand each other but Origami told her that she will reject all Spirits, including herself.
At the end of Volume 11, their relationship has improved slightly with Origami no longer considering Tohka an enemy. She still, however, considers her as a rival when it comes to Shido's affection. As revealed during Volume 12, she still constantly tries to beat her at everything, even though she refuses to admit it.
Kotori Itsuka Edit
As Shido's sister, Origami considers Kotori to be her future sister-in law. However, after seeing Kotori's spirit form in Volume 4, she immediately rushed to use forbidden technology in attempt to kill her. This was due to believing that Kotori was the spirit who had killed her parents 5 years ago. Their next major interaction was during Volume 12. Suspicious of Kotori's unusual behavior, she followed her and once again threatened to kill her when interrogating her of the plans to kill Shido. However, she did show sympathy for Kotori after seeing her crying face, noting that she was still a good sister after Kotori made a self-deprecating comment.