Coven' has been used as a collective noun for vampires, possibly based on the Wiccan usage. An alternative collective noun is a 'house' of vampires. David Malki, author of Wondermark, suggests in Wondermark #566 the use of the collective noun 'basement', as in "A basement of vampires."Origins of vampire beliefs
Le Vampire, lithograph by R. de Moraine in Féval (1851–1852).
Commentators have offered many theories for the origins of vampire beliefs, trying to explain the superstition - and sometimes mass hysteria - caused by vampires. Everything ranging from premature burial to the early ignorance of the body's decomposition cycle after death has been cited as the cause for the belief in vampires.
Although many cultures possess revenant superstitions comparable to the Eastern European vampire, the Slavic vampire is the revenant superstition that pervades popular culture's concept of vampire. The roots of vampire belief in Slavic culture are based to a large extent in the spiritual beliefs and practices of pre-Christianized Slavic peoples and their understanding of life after death. Despite a lack of pre-Christian Slavic writings describing the details of the "Old Religion", many pagan spiritual beliefs and rituals have been sustained by Slavic peoples even after their lands were Christianized. Examples of such beliefs and practices include ancestor worship, household spirits, and beliefs about the soul after death. The origins of vampire beliefs in Slavic regions can be traced to the complex structure of Slavic spiritualism.
Demons and spirits served important functions in pre-industrial Slavic societies and were considered to be very interactive in the lives and domains of humans. Some spirits were benevolent and could be helpful in human tasks, others were harmful and often destructive. Examples of such spirits are Domovoi, Rusalka, Vila, Kikimora, Poludnitsa, and Vodyanoy. These spirits were also considered to be derived from ancestors or certain deceased humans. Such spirits could appear at will in various forms including that of different animals or human form. Some of these spirits could also participate in malevolent activity to harm humans, such as drowning humans, obstructing the harvest, or sucking the blood of livestock and sometimes humans. Hence, the Slavs were obliged to appease these spirits to prevent the spirits from their potential for erratic and destructive behaviour.
Common Slavic belief indicates a stark distinction between soul and body. The soul is not considered to be perishable. The Slavs believed that upon death the soul would go out of the body and wander about its neighbourhood and workplace for 40 days before moving on to an eternal afterlife.
Because of this, it was considered necessary to leave a window or door open in the house for the soul to pass through at its leisure. During this time the soul was believed to have the capability of re-entering the corpse of the deceased. Much like the spirits mentioned earlier, the passing soul could either bless or wreak havoc on its family and neighbours during its 40 days of passing. Upon an individual's death, much stress was placed on proper burial rites to ensure the soul's purity and peace as it separated from the body. The death of an unbaptized child, a violent or an untimely death, or the death of a grievous sinner (such as a sorcerer or murderer) were all grounds for a soul to become unclean after death. A soul could also be made unclean if its body were not given a proper burial. Alternatively, a body not given a proper burial could be susceptible to possession by other unclean souls and spirits. Slavs feared unclean souls because of their potential for taking vengeance.
From these deeply implicated beliefs pertaining to death and the soul derives the invention of the Slavic concept of vampir. A vampire is the manifestation of an unclean spirit possessing a decomposing body. This undead creature is considered to be vengeful and jealous towards the living and needing the blood of the living to sustain its body's existence.
Although this concept of vampire exists in slightly deviating forms throughout Slavic countries and some of their non-Slavic neighbours, it is possible to trace the development of vampire belief to Slavic spiritualism pre-existing Christianity in Slavic regions.