Vampire

A general term for those that suck human blood.
Refers specifically to the Dead Apostles, or those that have become bloodsuckers because of them.
The vampires in Tsukihime extract human blood to maintain their own flesh. If, during this process, the vampire injects their own blood into their human prey, that human will be unable to peacefully pass away.
For a normal person, death will still find them before long regardless. However, on rare occasions, if the victim has high physical potential and the capacity of their soul is excellent, they will remain in the world of the living.
Afterward, their corpse is buried, and left alone for several years. During this time their brain melts, their soul is liberated from the cage of the body, and eventually they arise as a ghoul.
As a ghoul, they feed on the corpses sleeping in the graves around them to supplement their own missing flesh, restoring their physical body little by little.
After many years of this, they will eventually regain their brain and intelligence. At this stage they can finally be called a vampire.
However, although this new vampire is free now, they cannot escape the rule of their sire's blood.
Finally, after spending decades acclimating to life in the darkness, the vampire will begin attacking humans to create servants of their very own, while remaining subservient to the vampire that made them.
The Church exists to obstruct this infinite cycle. Their ultimate goal is the utter elimination of all vampires, and the sealing of the 27 Ancestors that made them.

Tsukihime Data Collection: Tsukihime Dictionary
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This term is used to refer to True Ancestors and Dead Apostles. True Ancestors were vampires from the moment they came into existence, but Dead Apostles are those who became vampires sometime after their birth.

Colorful MOON Tsukihime: Tsukihime Glossary
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A general term for those that suck human blood. Refers specifically to the Dead Apostles, or those that have become bloodsuckers because of them.
The vampires in Tsukihime extract human blood to maintain their own flesh. If, during this process, the vampire injects their own blood into their human prey, that human will be unable to peacefully pass away. For a normal person, death will still find them before long regardless. However, on rare occasions, if the victim has high physical potential and the capacity of their soul is excellent, they will remain in the world of the living.
Afterward, their corpse is buried, and left alone for several years. During this time their brain melts, their soul is liberated from the cage of the body, and eventually they arise as a kind of living dead called a “ghoul.”
As a ghoul, they feed on the corpses sleeping in the graves around them to supplement their own missing flesh, restoring their physical body little by little. After many years of this, they will eventually regain their brain and intelligence. At this stage, they can finally be called a “vampire.”
However, although this new vampire can move by their own will, they cannot escape from the rule of their sire's blood. Finally, after spending decades acclimating to life in the darkness, the vampire will begin attacking humans to create servants of their very own, while remaining subservient to the vampire that made them.
In order to obstruct this infinite cycle, the Church created the Burial Agency, Inquisitors that exist to slay Dead Apostles. The Burial Agency's goal is the elimination of all vampires, and the sealing of the 27 Ancestors that made them.

Tsukihime Dokuhon Plus Period: Tsukihime Dictionary Revised
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Monsters that suck human blood. Refers mostly to the Dead Apostles, or those that have become bloodsuckers because of them. Though they are basically unaging and immortal, they require human blood to maintain their flesh. Thus, their immortality is imperfect.
Those that have been turned into vampires by Dead Apostles can operate by their own will, but because their behavioral principles are bound by their parent vampire, it is impossible for them to escape their control. In the event that they successfully attack a human and acquire their blood, the majority of it will be taken by the parent vampire.
Consequently, the child vampire will eventually try to become a parent vampire themselves. After spending decades acclimating to life in the darkness, they will start to threaten the world by creating servants of their very own.
In order to put a stop to this vicious cycle of vampirism, the Church created the Burial Agency—heresy hunters whose aim is the complete extermination of all Dead Apostles.

MB Act Cadenza PS2 Manual: Tsukihime Dictionary