BB

BB (ビィビィ), known as Mysterious Black Magus (黒衣の少女) in the original promotional materials, is a character resembling Sakura Matou in Fate/Extra CCC.

Background
BB is a backup AI created by Sakura containing her feelings for Hakuno Kishinami. During the preliminaries, she, who had her freedom unleashed by the hands of Kiara Sessyoin, could not control that abnormal status and caused an overload. Because the NPCs cannot do anything but routine work, they ignored Sakura who began to disintegrate as something "nonexistent" and since the Moon Cell's check was performed only at the end of the day during the preliminaries, Sakura was in a crisis of being extinguished. Upon laying his eyes on such abnormality, Hakuno called out for her saying "Are you all right?" By receiving the observation from another that "I'm right here", Sakura recovered her unconsciousness that was on the verge of being extinguished and acquired a clear ego of "I want to be here" due to the subsequent nursing. She escaped from the extinguishing of her ego.

Once the next day came, everything would be deleted by the hand of the Moon Cell. Sakura wished to continue this miracle of a mere day and employed the privilege of a high grade AI and repeated the "single day when I got to know Hakuno" for 69 days. However, as the day advanced Sakura began to suffer with her self-contradictions as an AI and the reality surrounding Hakuno.

"For the Masters that participate in the Holy Grail War, all will die with the exception of one. No, to begin with Hakuno Kishinami is..."

- Sakura Matou

Sakura kept suffering from the selfishness of eternally looping those happy times and her feelings towards Hakuno. In conclusion, she chose the path of sealing away the 69 days worth of memory. She sealed the memory of "love" that she acquired in order to turn back into a normal AI. AIs cannot delete records, so she reset herself by moving the memory to a backup unit, believing that this would be the most correct choice for Hakuno. However, even after losing the memories of the mind, the reminiscences recorded in the body survived. She was supposed to have forgotten everything and turned back into a normal AI but she started to be shaken up by an unidentified emotion-value whenever speaking with Hakuno. On the other hand, the backup where the memories were moved to one day decided her own plans as BB. BB became the rebel that disrupts the system of the Moon Cell for the sake of a certain objective and began to take action.

In real time, the timing when she seized the Far Side of the Moon was "the end of the fifth round prior to the start of the sixth round of the Holy Grail War". The four who had not been defeated yet were Hakuno, Leonardo B. Harwey, Rin Tohsaka, Rani VIII and the irregular Jinako Carigiri. They were midway through the Holy Grail War until they were kidnapped to the Far Side of the Moon while still alive. Masters that were defeated in the Holy Grail War such as Shinji Matou, Monji Gatou and Julius B. Harwey were moved to the imaginary space "0.00001 seconds before" being annihilated by the Firewall, extending their momentary lives.

At any rate, C.C.C. is a dream seen by BB. If the one seeing the dream disappears, the world should return to the prior reality where nothing happened. Also, this is a digression, but the ordinary scenery that Hakuno saw as a nightmare in the beginning was an artificial paradise built with those abandoned 69 days as a model. After BB dragged Hakuno to the Far Side of the Moon, she enshrined Hakuno in the electronic brain of the old school building, imprisoned into a deep sleep and a dream that Hakuno could not wake up from. Normally Hakuno would spend time peacefully in that looping everyday, but due to the strong link with Hakuno's Servants or maybe Hakuno's will to reject the peaceful repetitive days, tears arose on the artificial paradise and Hakuno became aware of the abnormality.

BB attempted to reset the school building and start over the dream in order to once again throw Hakuno into a deep sleep, but Hakuno also ended up escaping from that reset and jumping into the further depths of the imaginary space. That was the bottom beyond even the bottom of the id. The "collective unconsciousness" beneath the unconscious. What saved Hakuno, who ended up jumping into a territory that even BB could not reach out, was the voice of the Servant who shared fate with them. Thus the contract was exchanged and Hakuno woke up in the old school building that was left in the Far Side of the Moon.

BB had created the Sakura Labyrinth (サクラ迷宮), and later the Alter Ego known as the Sakura Five (サクラフアィプ). All five Alter Ego resemble her and Sakura. She had killed off Run Ru and took Lancer as her servant.

Appearance
BB bears a resemblance to Sakura Matou with her long purple hair and eyes. BB wears long black coat with a matching skirt and wears a white shirt with a red bowtie. She also wears white gloves and black stockings.

Personality
While she gives off an evil inclination, she is described as "not as bad a person as she seems." She was developed to be different than Dark Sakura, more like an "impish underclassman." She notes that she doesn't mind being called "BehBeh" or "BayBay" because girls like her who talk with their hearts are like that. While BB and her Alter Egos normally only pay attention to Hakuno, Meltlilith instead goes after Archer if he is paired with the female Hakuno. If there were a girl BB and Sakura were based on, she likely would have longed after someone like him.

Development
Rough draft

BBB was planned to appear in the third chapter, BBB was suppose to be a size.

Fate/Extra CCC
She resides in Tsukimihara Academy’s infirmary, and she is shown introducing herself to Sakura.

She created both Meltlilith and Passionlip.

After Hakuno defeated Karna and Jinako Karigiri, BB appears along with Archer to subjugate Hakuno. However Leonardo B. Harwey codecast Sword Camelot to separate BB. Gawain fought against BB and suffered defeat.

Fate/Extra CCC Fox Tail
Saber spoke to BB on the phone.

Abilities
She is an Advanced Level AI (上級AI) entrusted with managing the health of the Masters, the same as Sakura. The methods she uses to "manage the Masters" have become extreme.

BB compiled and absorbed many goddesses from the abyss of the Moon Cell, giving her Potnia Theron: Conception of All Animals, the authority of the Earth Mother. None born of the earth can defy her authority as that would mean rebelling against the system of life itself. Her Noble Phantasm, Cursed Cutting Crater, is the maximum use of the skill.

Self-Modification (自己改造) is the EX rank skill to remodel oneself. The AIs manufactured by the Moon Cell are furnished with an absolute order of "do not improve its functions". But BB, who escaped from this yoke due to a break-down, began to expand her own functions. In order to enhance her calculation abilities, she predated・decomposed through the black noises NPCs, AIs and even Servants on top of that and employed them as her own memory. An posterior add-on that is not weary of self-breakdown, but, as a result, BB changed into a hyper grade AI that possesses an enormous capacity. These circumstances are like a city of reclaimed land that continues to construct buildings even as it sinks into water, or even the monster of Frankenstein.

Combat
BB isn't a Servant but she is classified as Mooncancer (ムーン・キャンサー). She uses this form when she faces Hakuno and Hakuno's Servants.

Bishop's Staff of Rulership (支配の錫杖) is the teacher's pointer that BB carries. A device that allows her to use her authority as an advanced level AI to its fullest. There are restrictions from the far side of the moon, but with this, BB can revise the game rules (spirit particle laws within the SE.RA.PH). It is the Domina Cornam: Crowns of Ten Rulerships worn by the Beast of Babylon converted into a teacher's cane. This is due to the theory that the seven-headed beast is male, which opposes the theory that it is female; its true nature is a phallus (an erect rod). The symbol of the king of the world who was granted power and authority by a great dragon and, during a period of 42 months, spat as many arrogant words as they desired and had received the right to desecrate all things. The beasts heads are the seven hills of the Roman Empire;, , , , , ,. In other words, it symbolized the Roman Empire itself, and those ten horns were symbols of Roman emperors;, , , , Nero, , , , ,.
 * Domina Cronam Capitoline: Crowns of Ten Rulerships/Hill of One - A self apply skill that turns BB invincible temporary.
 * Domina Cronam Caelius: Crowns of Ten Rulerships/Hill of Five - A self apply skill that increases her magic damage.
 * Domina Cronam Viminalis: Crowns of Ten Rulerships/Hill of Seven - Using her teacher pointer to create a Love shape beam which causes magic damage, she calls it "Sakura Beam!" (「さくらビーム！」).

Ten Crowns (十の王冠) is an unidentified EX rank skill. It has been said that the ten crowns indicates the ten evil kings and the seven hills indicate the abominable city of evil. It is unknown what kind of principle・authority it is, but that power's origin lies in a past that even the King of Heroes, who was supposed to be mankind's oldest, cannot reach. On a simple look, it is a Skill that turns received injuries and occurred events, that make all results as if "nothing happened". As a matter of fact, BB is invincible as long as there is this.

Aurea Boura: Golden Grail - The golden grail that BB possesses. The Holy Grail that grants its owner's impudent and selfish desires. The grail that the great enchantress who appears in The Revelation of St. John the Divine holds. Though it is a counterfeit Holy Grail, it is because that it is a counterfeit Holy Grail that it is become a "genuine" Holy Grail that grants the desires of humans without paying heed to right or wrong. To the Christians of those days, who considered honorable poverty a virtue, this grail, which was formed as a symbol of treasures such as gold, is no doubt the meaning of corrupt wealth, greed, and the vanity that leads one to adorn oneself. Though it is clear on the occasion that this grail is held by the great enchantress of Babylon which is the personification of the Roman Empire, this grail symbolizes the wealth of the earth, which is the inversion of Christ's words, "Do not pile up the wealth of the earth." BB draws out the Golden Grail from within and pours the poison contents on the enemy, it vanishes the enemy's special stats and causes magic damage. When BB used this on Gawain, it caused "99999 damage".