|Spoiler Alert: This article/section contains details about future plot lines described in the light novels, not covered in the anime. Do not proceed unless you want to be spoiled.|
|Novel Debut||Date A Live: Ren Dystopia (Novel)|
|Game Debut||Date A Live: Ren Dystopia|
Ren wears a stylish purple Astral Dress with bandages covering her arms and eyes. She has a visible scar over both eyes that resembles the makeup of a clown. Her purple eyes match her long purple hair that is decorated with floral patterned ribbon ornaments and a small top hat with light pink frills at the bottom. Additionally, she has shackles with long chains that bind both her arms and legs together.
After stealing Reiryoku from all the sealed Spirits, Ren gains a dark purple Astral Dress which exposes her navel and legs, the latter gaining markings on her thighs. She also gains two dark hairpieces, and a dark halo with upside-down wings floating behind her. Overall, her outfit looks like a more malicious version of Mio Takamiya's Astral Dress.
During her last kiss with Shido, Ren's hair color turns white for a brief moment before she disappeared.
Ren proclaims herself a "pitiful jester" and pledges servitude to whoever opens her Angel, offering to grant three wishes. However, she has a sly nature and often twists her contractor's words so that they will wind up dissatisfied with the wish and make another to fix the previous. After absorbing as much Reiryoku as she can from her contractor, she will turn on them with killing intent, proclaiming to have been born a villain.
Ren was born as the personification of Mio Takamiya's sorrow and hatred toward Isaac Westcott for killing her beloved Shinji Takamiya. Fearing that Ren would someday harm Shinji's reincarnation Shido, Mio sealed her and left her in the space between this world and the Neighboring World, but she was released when Shido changed history through Kurumi's <Zakfiel>.
Before her sealing, Ren made her first wish with <Samael> to meet Shido, for whom she had inherited her mother's love. However, she would forget this wish in the 30 years she was sealed, and while she still holds feeling for Shido deep down, she also desires to kill him out of spite toward her mother for sealing her.
Ren first appears in Shido's dreams, expressing joy that she has been freed from the gap between worlds. When Shido wakes up, he finds a mysterious purple box with golden snake decorations in his room.
While trying to locate the owner, Shido will present the box to the Spirit of that route, who will open it and find the box empty, though Shido will sense something emerging from it. Ren will begin visiting the Spirit's dreams to offer her three wishes, one per night. The following day, Shido will encounter Ren in the real world, inexplicably knowing her name on first sight. Ren will give implications toward the wish she recently granted before disappearing. After all three wishes have been granted, Ren will trap Shido and the Spirit in a pocket dimension, with the latter having their Reiryoku stolen by Samael. If all choices in the route have been done correctly, Shido will supply the Spirit with the other Spirits' Reiryoku (while the unsealed Kurumi will regain her Reiryoku after exposing <Samael>'s failure to properly grant her first wish), granting a complete Astral Dress and enough power to drive Ren away. Should any choice be made incorrectly, Ren will kill the Spirit before turning on Shido.
In Ren's route, Shido himself opens <Samael>'s box and becomes Ren's contractor. To Ren's surprise, Shido makes two mundane wishes to introduce Ren to the other Spirits and have her experience a day at Raizen High School. Before enacting her goal, Ren makes her second wish for <Samael> to make herself imperceptible to her mother, but is troubled that she cannot remember her first wish. When Shido gives his final wish for Ren to reveal her true intentions, she admits that she wants to kill him, trapping him in her pocket dimension and stealing his Reiryoku. However, his distress subconsciously sent some of the Reiryoku to the sealed Spirits, allowing them to regain their complete Astral Dresses and come to his aid. Unperturbed, Ren uses the stolen Reiryoku to manifest her true Astral Dress and create shadow clones of the Spirits. Shido and the girls are at a disadvantage until Kurumi arrives to help, using her own clones to distract Ren's. After Kotori informs Shido that Ren's affection toward him is enough to be sealed despite her current actions, the Spirits help Shido approach her for a kiss, ultimately succeeding by breaking Ren's concentration with a sudden love confession. With her powers weakened, the dimension starts to collapse with everyone trapped inside, but Ren uses her final wish to let them escape, bidding farewell to Shido as both her sworn enemy and friend. Afterward, nobody but Shido remembers Ren. Shido brings Tohka to the shrine where he first met Ren to wish for a reunion, and briefly hears her voice lightly mocking him for such a wish.
If Ren's route is revisited after clearing all the others, Shido's final wish to learn Ren's intentions instead becomes saving Ren in the truest sense. <Samael> puts the two in a parallel Tengu City for the sake of uncovering Ren's first wish, reviving Rinne, Mayuri, Rio and Marina (once again sharing a body with Maria) to serve as guides. Shido and Ren finds "fragments" scattered over the city which allow them to re-enact portions of the other Spirits' wishes, with Ren playing the role of the Spirit. Each time a "fragment" is found, the Spirit involved is brought to the parallel world. After having a barbecue with everyone, Shido is encouraged by Rinne to resolve Ren's issue and gives him <Samael>‘s box. As the two converse alone, Ren admits that she is afraid of remembering her first wish, despite previously denying it when accused by Marina. She finally remembers from her own fragment within the box that her first wish was to meet Shido and muses that it had already been granted, even though she encountered him as an enemy. The parallel world then begins to collapse, and Ren explains that the only way to rescue everyone in time is for Shido to seal her. Shido refuses, knowing that as a being of Reiryoku like her "sisters" Mayuri and Rinne, she will cease to exist. In response, Ren uses her final wish to force Shido into kissing her, causing her hair to fade to white, and she bids farewell to Shido as her beloved.
As Ren's body dissolves into light, satisfied that her first wish came true, Mayuri, Rinne, Rio and Marina assure her that the others have successfully escaped, as they will be disappearing along with the parallel world. The effect of Ren's second wish wears off, allowing <Phantom> to visit her in her last moments. <Phantom> apologizes for fearing her and sealing her away, but Ren admits that she no longer holds any grudge toward her. Her tearful last words are thanking her mother for giving birth to her. Afterward, Shido and the others no longer remember Ren or the Spirits in the parallel world, but they have vague memories of the experience as a supposed shared dream.
Powers and Abilities
Astral Dress: Unnamed
Samael takes the form of a small, seemingly empty purple box with golden snake decorations. The Angel functions as a "shell" to protect Ren from the gap between worlds where she was sealed. However, the person who opened it will start encountering Ren in their dreams, where she will offer to grant three wishes. One wish is granted per night, and takes effect when the contractor wakes up the next day.
However, Samael is a "poisonous" Angel that gradually absorbs the contractor's Reiryoku to empower Ren. This includes the portion of Reiryoku sealed by Shido; neither he nor Tohka could summon <Sandalphon> when the latter fell victim. As her powers are unsealed, her right eye and then her left eye are exposed. Once her power is unleashed, Ren can trap others within a pocket dimension. The "poison" scales in accordance to the number of wishes granted. For instance, Origami and her new timeline self were each granted two wishes, so neither suffered the full repercussions. In terms of limitations, <Samael> could not properly grant Kurumi's first wish to undo the First Spirit's existence, as Ren, being a Spirit, would not be able to continue granting wishes. <Samael> instead erased all memory of Spirits existing, and Kurumi was reimbursed with all her stolen Reiryoku upon calling out the Angel for failing to truly grant her wish.
By stealing 8 Spirits' worth of Reiryoku from Shido, she regains her original Astral Dress and can create shadow clones of the Spirits whose Reiryoku she has absorbed which share injuries with the originals. She could not create clones of Kurumi, as Shido had only sealed a small portion of <Zafkiel>'s Reiryoku at that point. Ren herself is allowed three wishes toward her own Angel, seemingly without any side-effects.
- (To Shido Itsuka) “This is the world created by your desire. I will accompany you until you are satisfied. ──After this, destruction is unavoidable. I’m not petty enough to not put up with a celebration like this before saying goodbye.” 
- (To herself) "Then let's raise the curtains. To a tragedy of unending tears. To a comedy of unending laughs."
- (To Shido Itsuka) "Itsuka Shido, I──have always, always, wanted to kill you."
- (To herself) "From the beginning to the end, Itsuka Shido—I loved you as much as I wanted to kill you.”
- (To Shido Itsuka) "Farewell... Shido. My archenemy. My sworn enemy. My──friend."
- (To Shido Itsuka) "Good grief, to use your valuable wish in such a way. You truly are—incorrigible."
- (To herself) "That wish was—please, let me meet that person. That beloved person floating in my heart."
- (To Shido Itsuka) "I'm reluctant to say this, but this is the end. It was brief, but really──enjoyable. ──Goodbye, Shido. My beloved." 
- (To Phantom) “…………What are you saying? I am no longer angry at you. Without your hatred, I would never have met him. The days spent in this world were so much fun that I forgot about those 30 years in the dark. That’s why──thank you for giving birth to me. ──Mother.”
- Samael means "Poison of God", fitting the poisonous nature of the Angel.
- Ren's name means "lotus", a flower which is considered sacred in Indian religions.
- Ren's Spirit number is zero, which is derived from her name being pronounced akin to the Cantonese reading for the number zero.