The virudrei /ˈvɪɹoʊdɹeɪ/ is a stranger whose tubular structure resembles a circulatory or nervous system without a surrounding body. Its central "spine" branches off into dozens of rubbery veins, each one filled with an acidic, metallic fluid. Its three to five legs extend asymmetrically, which causes the virudrei no loss of balance. It seems to float upright rather than stand, its feet only just resting upon the ground.

The virudrei's surface is reflective, as are the eye markings, which hang down amongst the veins. Though slick and gooey to the touch, the eyes leave behind no stickiness when touched. Despite the virudrei's seemingly rubbery nature, its body conducts electricity readily.

Although they do not stretch, each of the virudrei's vessels can tolerate significant pulling and yanking, and indeed, cannot be snapped by human strength. They can instead be cut by a knife, or (most easily) a pair of scissors. Cutting the tendrils elicits neither regenerative nor averse response, and the virudrei can lose up to 80% of its threads with no loss of integrity. Death by vein-clipping occurs with an abrupt limpness, too sudden to allow the virudrei time to respond.

The virudrei does not broadcast its voice using audio waves, but instead communicates via cellular signal. (see effect upon cellular signals.)

Under normal conditions, the virudrei is bone white, with goldenrod eyes. Individuals that generate within coagulated pockets,^ℹ however, display distinct cruotypes.

An environment generates virudrei when one of the following events occurs there.

The more times an event occurs, the more the environment becomes primed for further infestations. The virudrei's generating territory can span up to a four hundred foot radius; within these spaces, the stranger tends to spawn beneath cover and near electronic devices. When possible, it generates atop a cable.

It shimmers into view, starting thin and spreading outwards in a bloom, mature within the half-second.

The virudrei's body slips through any quarter-sized hole to thread through classrooms, call centers, and supermarkets. Its attention is stirred only rarely, any curiosity directed solely towards structural details. An unusually angled wall, a panel beneath a window, or a section of drop-ceiling may cause it to raise its head or twine its veins forward, with particular planes causing a wave of timid, but evident convulsions.

As the virudrei wanders, it is drawn towards cellular activity, and it may even linger around areas with a high signal saturation. It rests (its body splayed and unmoving) for no more than a few hours though, returning to its course with renewed restlessness. Likewise, just as the virudrei is drawn towards cellular activity, it avoids areas in which signals are dampened, blocked, or nonexistent.

When two virudrei come within 0.67 miles of one another, a pairing response occurs. One follows the other at a distance, while the leader (usually, the younger of the two) seeks out an enclosed refuge. It is most likely to seek an irregular space caused by decay or collapse (such as a gap inside a crumbling wall, or a crack beneath an abandoned roadway), and prefers as small an entrance as possible. The leader spends only three hours and seventeen minutes searching for such a gap, however, and virudrei that do not locate an ideal location may instead compress themselves a discarded cabinet or empty metal barrel, though stability drops rapidly in such suboptimal shelters. When a pair fails to find any suitable space, both die with a limp, downward tug.

Virudrei do not leave the newfound nest, but instead writhe, tangle, and untangle themselves, alternating between periods of high and low activity.

The coil draws further virudrei in, affecting a radius of 0.67 miles. These new virudrei add their bodies to the snarl, which shifts to accommodate the newcomer.

A wandering virudrei disrupts cellular signals within a 0.67 mile radius. The nature of this interference varies between individuals. Some virudrei possess voices that sound like a long, droning pitch, while others sound like a cavalcade of voices. Others have high and intermittent voices, some the same looping tone, or merely static. Some virudrei mirror back what the speaker says, and still others speak through mechanical number strings.

Within a nest, each subsequent virudrei increases both the range, strength, and variance of the tangle's effects, with up to an 8.2 mile radius at 106 individuals.

Though a roaming virudrei does break off all pursuant behaviours when it meets a sensitive, and retreats from violence to itself with a twitching crumple, it otherwise displays little overt care towards a sensitive's presence.

The virudrei is dangerous when either physically interrupted in their braided nest, or when a sensitive makes a cellular phone call within the virudrei's line of sight. In these instances, the stranger responds with aggression, causing a "serosangre bleedout", whose primary symptom is massive cranial hemorrhaging.

Such a bleedout is inevitably fatal.

As a stray virudrei ages, its tendrils grow limp one-by-one, and its posture sags. Its behaviour does not change, however, and instead, the virudrei dies suddenly, leaving behind its limp corpse.

Healthy virudrei exponentially raise each others' stability and lifespan, and as such, the death of the individual (though not exceptional) tends to be postponed until the mass death of the group. Once a nest of virudrei becomes so clogged that movement becomes impossible, so too does the tangle's stability begin to drop. Some virudrei begin to twitch and writhe, while others constrict themselves further. When the group finally dies, it does so with a final signal burst, dropping all calls within the territory, and, in the case of truly grand nests, incurring a fatal serosangre bleedout on all sensitives within range.

A dead virudrei's decomposition at first mirrors the degradation of the rubber tubing it imitates, until after several hundred years of slow drying and crumbling, its body fades away with a fuzzy radiance and leaves no trace behind.

Virudrei never use the same nest twice.