Sariel

Sariel is the former 7th Apostle. In truth, she is Shirasaki Yuriko Kurono Maou's former classmate in Japan.

Appearance
She has long silver hair and brilliant red eyes. She is described to be rather short and to possess soft white skin.

Personality
She has a really cold personality, resembling a lifeless doll.

Plot
She first appeared alongside cardinal Ars while making a visit to the White Sacrament Third Laboratory to discuss about the "Holy Soldier" project. During the meeting with some of the researchers an earthquake occured, in which Kurono Mao got free, at this point Sariel decided to go after him.

Kurono, Lily, and Fiona team up to fight Sariel. Fiona seals them off into basically another dimension related to her God, meaning that the Divine Protections of other Gods are way weaker than normal if not completely unusable. Lily uses a special fairy magic that fused her and Kurono into a single body, and able to both control the body while also using both their magic attributes (ordinarily Kurono is only able to use Dark attribute magic, while Lily is only able to use Light attribute magic). Kurono manages to cut off one of Sariel's arms, one of her legs, and then the foot on the other leg; but an artifact that Sariel has activated opening a teleportation gate. Because Sariel is an Apostle, she'll regenerate her arm, leg, and foot if she escapes and has time to heal, so Kurono jumps in after her.

Kurono knowing that Sariel is also an experimental subject purposefully uses magic that will unlock the seal on her memories in order to break her concentration for just a second so he can finish her off, but because of the link between the magic he cast and himself, he sees her memories in reverse from the most recent to the oldest. Both of them are seeing visions of Sariel killing off experimental subjects one after another, Sariel is still crawling away with Kurono chasing after her in the meantime while the memories continue in rewind. As Kurono is choking her to death the memories go back to the very beginning. Sariel was actually made from the soul of Yuriko (the girl from Chapter 1 who was going to confess to Kurono). Kurono monologues about how he was prepared to kill Sariel, even knowing that she was an experimental subject like him, and was probably an innocent person who was kidnapped, tortured, and brainwashed, and was still willing to kill Sariel knowing all that, but can't bring himself to kill Yuriko. Kurono recognizes the forest they've been teleported to as the same forest where he met Lily, and carries Sariel back to their home. Sariel warns him that if he lets her live long enough to heal, her Divine Protection will force her to kill him. Kurono asks Sariel if she's a virgin while thinking to himself that's awful, and she tells him she is. Basically he's betting on the fact that maybe by making her not a virgin, he'll break one of the conditions that allows her to receive the Divine Protection of the White God. He tells Sariel that he won't kill her, but he won't let her kill him either, and that both of them will live. (NTR time) He laments over the fact that he's betraying Lily, having sex with their enemy in the precious home he had so many important memories with Lily in. He casts aphrodisiac magic on himself basically, and the scene ends. His gamble works though and Sariel loses the Divine Protection of the White God, which also means she seems to lose her super human regeneration so she's unable to regenerate her missing arm and leg.

Since Sariel and Kurono are now stranded in Crusader territory, Kurono pretends to be a Crusader Knight who had deserted the battlefield, and Sariel was his younger sister who was grieviously injured by a powerful knight of Spada. Kurono then makes a deal with one of the crusader villages that he would protect the town until the winter ends, and in exchange they would take of food/shelter, and would let him live undercover as a priest. Of course there are people in the village who notice that he's bull shitting as a priest because he doesn't know any of the scriptures or anything, but that Sariel does. The children seem to be under the impression that Kurono was a Knight of Spada who fell in love with Sariel a priestess, and that they had eloped and fled the battlefield. Fast forward to finally reuniting with Lily and Fiona, he explains what happened to them, and Lily runs off crying, when Kurono tries to run after her Fiona stops him and tells him that he isn't in the position to comfort her, and he can't bring himself to argue. Fiona then uses the opportunity to blackmail him into dating her. She told him that if he didn't become her lover, she would team up with Lily and they would kill Sariel. Kurono is quite emotionally vulnerable at this point and agrees. Fiona makes him let her take care of Sariel's needs from now on (Sariel is still missing an arm and a leg), and while Kurono isn't there forces Sariel to eat off a bowl on the ground like a dog, then puts her foot on Sariel's head while she's eating so that soup gets all over her, but then says that Sariel doesn't have to worry because this is the only time she'll be doing it. She's really upset that Sariel was the one who took Kurono's virginity, but that Kurono would hate a petty woman who bullied other girls. Fast forward a bit later when Sariel finally has her arm and leg regenerated with very expensive magic and Kurono receives a message from Lily, an invitation to the marriage of himself and Lily (yes, one person in the marriage is only being told now that they're getting married and the date is already decided), she tells Kurono not to worry and that she'll come to pick him up later. Fiona drugs Kurono and has had him sent away while he's unconscious, while Fiona and Sariel go to stop Lily. Lily in the meantime has gotten her Divine Protection from the fairy queen buffed up and is told that she's the first Fairy in thousands of years to finally discover "True Love" and is given the title of Fairy Princess as well as a trial, both a Divine Trial, and a "Trial of Love". If she completes it she'll directly ascend to Godhood. However even without having ascended, she is described as the "closest to God" even moreso than the Apostles, and that she's basically only a single step away from a genuine God. Furthermore, she has copied versions of all of Kurono's Divine Protections that were given to him by Demon King Mia Elroad. Kurono's are named things like "Demon King of Fire" and Lily's versions are named like "Queen of Fire".

Basically after Lily solos everyone else, Lily asks Sariel how she feels about Kurono slowly getting Sariel into her tempo. Lily mindfucks Sariel at this point. Lily points out that "the one whose name Kurono was yelling during sex was Yuriko's. The one who Kurono was embracing was Yuriko. The one Kurono was trying to save was Yuriko. Even knowing that Yuriko is gone, her persona completely erased, and all that was left was a wreckage in Sariel, but Kurono was so unwilling to sever the connection with her that he couldn't bring himself to kill Sariel. Kurono needs Yuriko, not YOU, not a doll of the White God named 7th Apostle Sariel." Lily convinces Sariel to start acting like Yoruko, after all, Sariel still has all of Yoruko's memories. So even if their personalities are different, she has the exact memories of how Yoruko smiles, how she laughs, how she acts when this or that happens. Sariel ends up trying it, and does an amazing job of it, while Lily keeps egging her on, and telling her that Kurono will be happy, that she should just pretend that by some miracle Yoruko's persona managed to survive and was finally brought back out. Sariel eventually breaks free of Lily's suggestion and fights back but is defeated. Lily is purposefully not killing anyone because her plan is to seal Kurono away for a thousand years. After a thousand years, everyone Kurono hated, the crusaders, the apostles, etc, will have died. And so will everyone he loved (except her), and so she will be the only thing he has. She's purposefully letting them live because if Kurono knows they lived out a full life, he won't be as angry at her and will continue loving her sooner. If she killed them instead, he will be angry at her for a long time first, and she would be sad during the time it takes for him to forgive her for killing everyone