18. Lappertapper
There are creatures known to witches and wizards, written about in works on magical beasts, sold in the quaint shops of Diagon Alley and its darker sibling, that can be thought of as magical only by association with this hidden world that Muggles know so little about. While they are used in intricate magic or occult rituals, the creatures themselves are merely unusual, lacking any innate magic. They are listed in magical texts but have thus far eluded the thorough cataloguing of Muggle biologists. It has been said that any sufficiently advanced form of technology is indistinguishable from magic. The same could be said for these queer creatures, known only to such a very small subsection of humanity.
One such creature is the Lappertapper. Miniscule enough to remain invisible to any eye that does not seek its presence, the Lappertapper exists only in colonies of thousands, each of them working as a synaptic node so that the colony can function as one creature.
Parasitic by nature, these weird creatures invade the oral cavity of their host. They prefer placement on the tongue, but once it is claimed, they will spread beyond its borders, sticking to any soft surface available.
Once established inside a host, the Lappertappers tap energy from the host's food, sucking vitamins, minerals, fat, and even magic from any organic material coming into contact with them. There are variants that tap till the food loses all its nourishing power but these are aberrations. Such mutations never survive to increase their numbers since their hosts die much too quickly. The common Lappertapper, however, weakens its host over a long period of time, thus having ample chances to migrate to a new host – during a failed act of mouth-to-mouth resuscitation if not sooner.
Lappertappers are only – illegally – sold in Knockturn Alley.
—from Essays on the Dark Side by Charles Wist, 1987