Main Story
The first true chapter illustrates a short introduction - Over the next few years between Lisanna's supposed death and the Oricon Seis Arc, The Rune Knights develop a special detachment for hunting down Ghouls, called "Black Runes" due to their more grim job and darker nature in suppressing the "monsters that have come t plague Fiore." During her life on the run, Lisanna becomes something of a pupil to Rize, who in turn comes to see the One-Eyed Ghoul as something of an indirect spawn due to Lisanna's powers stemming from having been transplanted with some of Rize's organs. Even as the two accept that someday one of them may devour the other, they still have a kinship as Ghouls with Lisanna feeling that Rize is the only one that will accept her, as Lisanna has at this point eaten both humans and Ghouls as a result of Rize's personality rubbing off on her over the years. Rize and Lisanna both wear masks and cloaks during their hunting habits (while Rize's wardrobe is unchanged from her appearance in Tokyo Ghoul, when hunting she will wear white clothes with red highlights and an off-red mask with devil horns, while Lisanna's clothes will mirror Ken Kanaki's black combat gear, with a black hood and a harness-mask on her face similar to his, but without the image of a mouth with teeth.)
Lisanna, over time, has become much more cold and cruel, her personality becoming closer to that of Rize over time as the older Ghoul imprints on her and imparts her way of living onto Lisanna. However a core part of her still exists that trembles at the idea meeting her former Guild-mates again and seeing their reactions - which in turn is half gleeful anticipation of making them see what she has become, and half terrified shame at being condemned, her mind having fragmented between two distinct personas; a callous and sadistic one being her Ghoul half, and a nihilistic and melancholic one being what's left of her original self. Rize and Lisanna both receive code-names from the Rune Knights in place of their actual identities, which are unknown to them - Rize as the "Binge Eater" or "The Living Sin of Gluttony" due to her tendency to eat at least one human or Ghoul ever three days simply for pleasure, and Lisanna as the "Chimera" due to the lower pair of her Kagune's four tentacles being longer, rounder and more narrow then the flattened-out and wider upper pair, making it look as though she has a pair of wings and two serpentine tails. Her name also references her animalistic tendencies in combat when submitting to her Ghoul impulses, due to her Take-Over magic interacting with her Ghoul half. Lisanna also gains the nickname "One-Eyed Demon" due to her single Kakugan eye.
The rest of Earthland comes to see Ghouls as monsters in the years after their arrival, with Ghoul-hunting jobs becoming issued to some Guilds as S-Ranked missions - although killing is prohibited among Guilds, nothing stops them from capturing the Ghouls and turning them into the "Black Runes" brace of the Rune Knights, although the fact that the Ghouls are executed or in some cases experimented on tends to be kept secret, even from the main branch of the Rune Knights. In fact, only the leaders of the "Black Runes" know the true extent of the Ghouls, with the soldiers that make up the majority of the force being largely ignorant as to how Ghouls aren't all monsters or how they are being experimented on by the leaders of the rouge division . Eventually, after the end of the Oricon Seis arc, Fairy Tail has their first encounter with Ghouls and takes a Job to hunt some - a colony where roughly eight Ghouls are hiding.
In the second proper chapter, Lisanna and Rize are stopping by this colony when Fairy Tail mage Erza Scarlet arrives to try and pacify them - being unwillingly accompanied by Natsu Dragneel, Gray Fullbuster, Lucy Heartfiella (who was dragged along by Natsu), Wendy Marvel, and the two exceed-cats Happy and Carla. They defeat and capture one Ghoul wearing a rabbit mask - who ends up revealed to be Touka Kirishima once they defeat, restrain and unmask her, with Touka losing easily because she hesitates upon recognizing their Guild-marks as being the same as her long-lost friend Lisanna - and head to the den only to find it evacuated, with another Ghoul - Kazuo Yoshida - being fed off of by a woman in red-and-white clothes, with three other dead Ghouls laying across the room.
The masked woman unleashes her Kagune and reveals herself to be a Ghoul as well, which shocks and enrages the Fairy Tail mages at how a Ghoul could canabalize another of their own kind, with Wendy being terrified of them and the others calling them "monsters," which the captive Touka immediately takes issue with due to canabalizim being spat upon even by other Ghouls, as it signifies a true monster. However, when the woman steps into the light and the moonlight reveals the outline of her distinctive Kagune, Touka panics as she recognizes her as being Rize. The Fairy Tail mages don't recognize her by name, but become stunned, concerned and even slightly intimidated when Touka, for their convenience, reveals that Rize is the "Binge Eater" and "Sin of Gluttony" that devastated an entire village in the far west, having slain every mage that ever tried to kill her. Rize is bemused at the fame she has garnered, before denoting that they forgot an important part - she has a "shadow."
At this point, Lisanna makes her presence known, attacking the Fairy Tail mages from behind and tackling Lucy to the ground, unsealing the mouthpiece on her mask and managing to take a bite out of Lucy's arm. But before she can try to devour Lucy, an enraged Natsu attacks her, sending her sprawling. She prepares to fight back, but then sees Natsu's face and Guild Mark, recognizing him immediately, although Natsu doesn't recognize Lisanna due to her hood covering much of her hair and her mask covering everything on her face save her left eye. Even Lisanna's scent has changed so much that it is not immediately recognizable to Natsu, altered by her Ghoul nature and masked by the blood of those she has recently eaten.
The sight of Natsu and the expression of anger and disgust he gives her sends Lisanna into a breakdown as her mental image of Natsu loathing her Ghoul form comes true before her eyes, and she goes berserk, injuring him as her Kagune manifest and badly wounding Lucy with one of her tails when the Celestial Mage throws herself in the way of an attack that would have been fatal for Natsu. Natsu begins retaliating even harsher, grief-striken that Lucy was badly injured for his sake, and he and Lisanna come close to killing each-other as a result. Eventually, the Fairy Tail mages are forced to pull back, as Erza and Gray are soon injured by Rize as they fail to subdue her. Rize muses on whether to chase them or not, but decides against it as there is plenty of "food" still in the den and that she's rather hungry, with Lisanna gradually calming down and joining her, silent throughout the exchange as she tries to process the fact that she and Nastu - the boy she liked when younger - nearly killed each-other.
In the third chapter, As Lucy and Natsu are healed by Wendy, the mages all have a chance to talk with the captive Touka, who informs them, to their surprise, that not all Ghouls are evil in response to their criticisms of her. When Erza and Gray doubt this due to her kind eating human flesh, Touka shocks them all speechless when she reveals that Ghouls have no choice but to eat human flesh because regular food is indigestible to them - the only thing they can digest is human flesh - and as the confrontation between them mounts, she eventually begins to rage at them, crying while calling them the real monsters for having such a hate for her simply because of something she had no control over, having never asked nor wanted to be born a "flesh-eating Ghoul. Citing that she only ever wanted to live a normal life, Touka berates them by reminding them that just because there are Dark Mages out there that it doesn't mean all mages have the disposition to become evil and abuse their power, and that they have no right to assume the same of all Ghouls when the Ghouls have been treated as monsters for something they couldn't even control.
For a long moment after Touka pours her heart to them, the mages share an uncomfortable silence as they ponder the ramifications of what Touka has told them. After a few minutes, Wendy asks Touka if that was why Touka didn't eat Wendy when she had a chance during their fight, and Touka admits that this is only part of the reason - the other was the mark on their shoulder. Curious, the mages inquire further and Touka reveals that she knew someone with that mark who was her friend a long time ago, shocking them when she reveals it to have been Lisanna - although she doesn't tell them about how Lisanna was a Ghoul, as Lisanna herself had cited that she was afraid of them finding out what she was, and as such, the Fairy Tail mages assume that Touka had met Lisanna before the accident with Elfman in which she had been declared dead, as the Strauss siblings had passed through a village prior to their hunt for the Beast.
However, she does state that Lisanna told her that the mages of Fairy Tail accepted anybody so long as they protected their friends and were good people, but then bitterly denotes that the Guild must have changed since then since Lisanna had sounded skeptical of it - which infuriates Natsu as he claims that Lisanna would never have said that about the Guild. Touka presses that it is true since she had once asked Lisanna to take her there, only for Lisanna to refuse in fear - once again leaving out that Lisanna was a Ghoul herself and terrified of Fairy Tail seeing what she had become, her mind fraying and falling victim to insecurities such as doubt and fear as a result of hallucinations and night-terrors, all due to the deterioration caused by starving herself of human flesh. She does however admit that Lisanna saved her life, which also shocks the Fairy Tail members, who ponder whether or not Touka is telling the truth.
Eventually, after looking her over, Natsu states that he believes Touka, much to everyone's shock - including Touka's, who had little to no hope tay humans would believe her. As such, Natsu decides he wants to bring her to Fairy Tail so that they can at least learn more about Ghouls and see if they're not as bad as everyone states, which the others - Erza in particular - are against, but eventually they reluctantly agree. Touka gives them a warning though that the most a Ghoul can go without eating is two weeks, and since she had eaten right before they caught her, she ought to be fine for a while. Keeping this grim reminder in mind, the mages take Touka away after she makes them promise her one thing - that they warn the other Ghouls here about Rize the "Binge Eater" and the "Chimera" being here, as Rize eats other Ghouls.
In the Fourth proper chapter, Lisanna and Rize talk to each-other over the remains of the dead Ghouls they had killed in the den, where Rize cites that she noticed the mages that attacked them had the same mark as the red insignia on Lisanna's arm. Lisanna, hesitating when it's brought up, then tensely admits thats she knew them - or at least that she knew three of them, with the blonde girl and the smaller girl being unfamiliar to her, and that they were part her old Guild, Fairy Tail. Rize muses on this, remembering that last she knew, Lisanna said that her Guild thought she was dead, and asks of Lisanna plans to rectify that. Thinking it through a moment, Lisanna decides "not yet" - she wants to know how the Guild has changed before she does anything, but that there is one thing she definitely wants to do.
Elsewhere, Touka is introduced to Fairy Tail, much to the shock of the Guild as they had all assumed that the Ghouls were monstrous creatures, and already guarded due to Natsu, Lucy, Gray and Erza having been badly hurt by two Ghouls as evidenced by their injuries. Touka admits when questioned thats she does eat human flesh, but that no Ghoul is capable of digesting anything else so they have no choice. Natsu denotes that Touka is a "good Ghoul" and rather tactlessly blurts out that Lisanna had thought so and saved her life once, which shocks the Guild - especially Mirajane, who drops the tray of drinks she was serving. Touka explains that it was several years ago, allowing the guild to believe that Lisanna had met them prior to her supposed death at the hands of Elfman's Beast form. Makarov, perceptive as always, denotes that she is a kind girl and that Lisanna wouldn't have helped her if she didn't believe so either, if not bitter from how she was treated, and cites that he wishes to speak with her in private. Most of the Guild is apprehensive about letting a Ghoul speak to the Master alone, and Touka herself is worried, but she eventually complies.
When in private, Makarov astutely remarks that she isn't from Earthland at all. Shocked that he could know that, Touka admits that she and the other Ghouls came from a world called Earth (not the same Earth where Tokyo Ghoul series takes place, but rather a parallel of that world - one where Ken Kanaki didn't get turned into a half-ghoul because he never met Rize). He also asks what Touka's opinion of Lisanna was, and Touka admits that she thought of Lisanna as a friend who cared deeply about what her Guild thought of her. Touka then carefully asks what Lisanna thought of Ghouls, and Makarov cites that he never knew she'd known any until Touka came o the Guild, making Touka (mistakenly) assume that Lisanna had kept her Ghoul nature secret from her Guild-mates, before tentatively admits that one of the key reasons she came back wast to find out Lisanna's fate, which a saddened Makarov denotes that Lisanna was killed, likely just after saving Touka.
Touka is shocked and heartbroken by this, asking how she died, but Makarov doesn't say anything more then the fact that it was an accident involving her siblings. Saddened and grief-stricken that her friend is apparently dead, she thanks Makarov for telling her this, and Makarov cites that Lisanna has a gravestone she could visit if she wishes to pay respects to her. Thanking him again, Touka leaves, heading down into the Guild-hall with him and proceeding to answer the many questions - notably from Levy - about Ghouls.
