Fly Villiers

Fly Villiers is a Vampire and part of the same 13 Eastern European Families as Erika Amatsu.

Appearance
Fly is a small girl with jewel-like eyes and short silver hair. She wears a black military uniform consisting of a cap, a baggy jacket worn like a dress, stockings, gloves and boots.

Personality
Fly appears to have a sibling-like relationship with Erika, whom she refers to as "Queen". She considers Erika's stepsiblings, Satori and Ayumi, to be her siblings as well.

The illusion that Satori experiences shows more of Fly's personality, but it is unclear whether this is true of the real person. Fly is willing to spare an opponent in order to make a good impression on Satori, something that she would not normally do. Fly is also shown to enjoy fermented food and drink, using her power to ferment any that is served to her. She will do this even when it makes others uncomfortable.

Background
According to the Fly in Satori's illusion, she was born from adultery between criminal parents during an age of famine. The latter caused her to fight over fly-infested food, the only food available, with children in similar circumstances. The final meal she obtained in this manner killed her (presumably through food poisoning or a similar cause). Fly's body was not buried but instead left in the open, allowing it to be infested with flies. The three taboos that Fly had committed (being born to adulterous criminals, breaking food taboos, and not being properly buried) caused Fly to become a Vampire. Fly later became part of the 13 Eastern European Families.

Volume 7
When Satori is caught in the Bokor's illusion, he first sees Fly in the tunnel network under Kukyou City. Fly appears to save Satori and Ayumi from the illusionary Bokor. As a swarm of flies, she surrounds and decomposes the Voodoo monster (either the Bokor or his Zombie servant Akemi Sagawa), converting it to liquid. She consumes only the contaminated portions of the liquid, leaving the Bokor and Akemi unharmed. Fly returns to her normal form and throws a doll containing the Class Rep's soul to Satori, recommending that he leave it to Erika. She then politely introduces herself and asks them to pass on a message to Erika: "The 13 Eastern European Families are starving for a chat over bloody tea".

Fly later arrives at the Amatsu residence. Fly discusses the activities of Hidden Cloud, a loose association of those who intend to rebel against the gods (while hiding her own involvement in Hidden Cloud). She fills in Satori on the nature of Vampire society, including the organisation of the 13 Eastern European Families, of which 8 members have sided with Hidden Cloud. Pretending that she is among the traditionalists, Fly asks for Erika's help. She then leaves.

However, Karen reveals Fly's deception to Satori, which allows him and the others to come up with a plan to lure all of the 13 Eastern European Families to the Starlight Kukyou multi-purpose building, and hence subdue all of them (traditionalists and Hidden Cloud members alike).

Fly meets up with Satori as he's heading to the building. Satori pretends he doesn't know of her deception and asks her about her history as a Vampire, which Fly explains. The two of them arrive at the building (being the last to arrive out of those involved) and enter the elevator. Satori reveals that he know's Fly's true allegiance and Fly attempts to attack him, but she is rendered unable to move when she hears the sound of flowing water. She is fooled into thinking that Satori had redirected water into the elevator shaft, and falls unconscious (unaware that Satori had merely played the sound of water).

Satori encounters Fly for real after breaking out of the illusion. Along with the rest of the 13 Eastern European families, she is in Public Kukyou First High School and fighting alongside the Amatsu siblings against the Bokor. She and Satori head to the scene of the battle and find that the Bokor has managed to control Karen. Fly is hit by the Valkyrie's spear and breaks into a swarm of flies. Satori is able to put up a fight against Karen, tells Meslayate to force her into another room and then has Fly corrode Karen's spear into sludge. They then defeat Karen and the Bokor.

Along with the rest of the 13 Eastern European Families, Fly escapes Japan when the time is right.

Abilities
Superhuman Strength: As a vampire, Fly's strength is twenty times greater than a human.

Superhuman Speed: Erika can move faster than any human.

Superhuman Regeneration: Fly can regenerate rapidly from any injury, unless it was caused by her weaknesses.

Fly swarm transformation: Fitting her name, Fly can transform into a swarm of countless silver flies. These flies carry putrefactive bacteria.


 * Accelerated decomposition: In this form, Fly can decompose both organic and inorganic substances. In the case of the former, she does this by surrounding her target to trap in heat and also transfer bacteria. She can rapidly decompose even a Voodoo-empowered monster, capable of surviving a direct hit from a train, into liquid. She can then drink the resulting liquid. When doing this, Fly can selectively consume only the contaminated portions to undo a Voodoo-induced transformation. This ability is compared to the use of maggot therapy to sterilise wounds. In the case of inorganic matter, she can decompose anything in her hands (even through her gloves) and can even turn pure gold into a black sludge.

Infection: Fly can transform humans into vampires by sucking a lethal amount of their blood (approximately 1-2 litres).

Vampire Weaknesses: As a vampire, Fly has a large number of occult weaknesses. She must drink blood to obtain energy and will starve to death without it. Sunlight burns her if she is outdoors, though not if she is indoors (and other types of light have no effect). Damage to the heart will immobilise her, and will outright kill her if done using a stake of ash or hawthorn wood. She can also be killed by conventional fire. She is also vulnerable to weapons made of consecrated steel or silver and/or soaked in holy water. She cannot enter a house or other dwelling without the owner's permission. She does not have a reflection in mirrors. She cannot cross flowing water if she is able to perceive it, and even the sound of flowing water affects her if it's realistic enough.