The ambidroni (/ˈæmbidroʊni/) is a light blue, tissue-like stranger with ten to thirteen evenly-spaced, small-footed legs. Its body is composed of a silky, thin, translucent material, which casts a dim glow on its surroundings. This material is so fragile that any physical contact with the ambidroni causes it to crumple and collapse onto the ground, and even faint air currents cause a slight crinkling of the ambidroni's surface in all but the stillest of rooms. The ambidroni's eye markings are opaque, and several millimeters thinner than the rest of its body.
The vast majority (87.5%) of ambidroni possess either feminine or child-like voices, while the remaining minority speak only in a sound resembling white noise.
The ambidroni appears in or near residential areas between sunset and sunrise. It generates indoors 96% of the time, and on rooftops or porches 4% of the time. When it first appears, it fades into view as a sheet of crumpled, tissue-like material, which rises up to form the ambidroni's shape over the course of 22-35 seconds.
The ambidroni manifests in groups 58% of the time, which appear in circular or crescent-shaped formations. An ambidroni will also generate a smaller ambidroni directly beneath it in 3.9% of instances. These "nested" individuals move, live, and die together, neither quite the same entity nor individuals in their own right.
The ambidroni's nature is quiet and unassuming, and it spends most of its time in a stationary position, its head pointed vertically and its body arched into a tent-like shape. When the ambidroni moves, it does not lift its legs, but instead, rotates and walks forward using only the motion of its feet, thus keeping its body level.
Rhythmic sounds cause the ambidroni to either sway back and forth or bob up and down, as though pulled from the tip of its snout by an unseen hand. As such, the ambidroni appears to "dance" in time with music, although even the ticking of a loud grandfather clock or the dripping of a faucet can be enough to elicit these rhythmic motions.
Because the ambidroni's form is so flimsy, it is common for individuals to be killed instantaneously when their bodies are caught on sharp corners, snagged by moving objects, or when they are pulled from their feet by a sudden gust of wind. When one ambidroni within a group is killed, nearby ambidroni stand over a fallen companion's point of death and emit a quiet whisper, as though hushing away their own bad thoughts.
The ambidroni has some unknown relationship with the moon, and glitters when exposed to moonlight (through an open window, for example). This shimmering effect is most noticeable during a full moon, and the ambidroni loses its glow altogether during a new moon.
When exposed to flame, the ambidroni sizzles and disappears, much like a burning strip of film. Its burning body does not grow hot, however, nor does it set alight objects that it touches.
Groups of ambidroni do not interact with each other in any physical manner, and instead whisper in undulating and circling turns in a voice that is both reticent and soothing to the ear. Five percent of individuals are able to control the brightness of their luminous bodies, and groups of these individuals dim and glow in slow, patterned waves.
Animals fascinate the ambidroni, and it always rotates to face them. The ambidroni approaches very small animals, such as insects and spiders, with a playful eagerness, and even pats its toes at cracks in the floor or at the edges of carpets to get them to emerge. The ambidroni strokes the surface of these small animals with careful, gentle caresses, and never attempts to grab them or pick them up. It displays aggression towards only the smallest of mites and newborn spiders, which it crushes beneath its feet with a happy squint of its eyes.
Despite its observant interest in all creatures, the ambidroni displays hesitance and moves away from large animals such as dogs, cats, or rats, as even a single errant swipe of the claws or curious bite can prove forceful enough to drag down and destroy the ambidroni's body.
The ambidroni displays some brief interest in animal corpses, but appears disappointed by their lack of movement, and instead only picks at the softest areas of the corpse with lackluster, disheartened motions.
The ambidroni is a shy stranger, and moves away from all sensitives who approach it, stopping only when it hits a corner, and displaying no further reactive behaviours. Despite its shyness, the ambidroni does approach sleeping sensitives, albeit with caution. The ambidroni always turns its body to face towards the person around which it circles, and each time its target moves or shifts their position in any way, the ambidroni, in turn, readjusts the angle of its body.
When able, the ambidroni walks up to certain sleeping sensitives and places its small hand in theirs, an action which poses some risk for the delicate ambidroni. This contact appears to comfort the ambidroni, its eye markings slightly narrowing, although it is not known by what metric an ambidroni selects individuals with which to hold hands.
Proximity to the ambidroni causes sensitives to cry in their sleep, an effect which is harmless, and is not accompanied by unpleasant thoughts or bad dreams. In turn, the sound of this sobbing causes the ambidroni to release bloody, holographic tears from its eye markings. These tears float upwards and leave small puddle-like shapes on the ceiling above, which fade away after several minutes. This behaviour occurs in response to all human crying sounds, including recordings and exaggerated fake sobs.
It is not uncommon for the ambidroni to appear in the bedrooms of individuals who die alone and in bed, and when this occurs, the ambidroni manifests on the bed itself, rather than on the floor. Groups of ambidroni gather in a circular formation, each placing one hand upon the body. These groups do not engage in any other actions, and instead watch over the corpse night after night, dying each morning and renewing themselves each evening in turn.
The ambidroni lives for only a single night. Once the sky begins to lighten and the stars fade from view, so too does the ambidroni's body begin to droop, and as the sun's rays pierce over the horizon, the ambidroni collapses to the ground. Its fingers twitch and its limbs struggle to pull itself upward, but with all strength and vitality drained, the ambidroni can do little but crumple shut its eye markings in serene contentment and shrivel away to nothing.
Despite this short lifespan, ambidroni infestations, like the merridronel, tend to be cyclical, and reappear night after night, each new cluster oblivious to their predecessors.