The peraderi /pɛrəˈderi/ is a huge, but lightweight stranger with pink, white, and black coloration and large hindquarters. Its rubbery "skin" is three inches thick, but remains soft and flexible, with a pearlescent sheen. Its body is filled with a soft, fluffy substance that is neither quite solid, nor is it liquid, but behaves like a cottony fog, breaking apart and dissolving when touched. Although this material feels cool to the touch, and creates the impression of appreciable resistance upon the palms, it leaves no residue behind, and cannot be grabbed. Only a shade below transparent, this filling flows outward in a liquid-like matter, imperceptibly heavier than air.

While the peraderi's skin resists rough tearing and abrasions, it is easily pierced, and this strain displays no healing ability. In addition, the peraderi's form is highly flammable, burning up to nothing in less then a minute when exposed to flame.

The peraderi's voice is simultaneously chime-like and trumpeting; a great pearly instrument resonated from a bell.

The peraderi makes its home near bodies of water, with beaches being its preferred home, followed by docks, shipping yards, and long, empty stretches of road that run alongside rivers or the sea. The peraderi's appearance is affected by its environment; peraderi that appear near fresh water tend to be darker-colored and more frail than those individuals that appear near sat water, while pollution causes the peraderi to take on a greasy sheen.

The peraderi starts off as a crumpled pile of pinkish material, which appears in the twilight hours just before dawn. This pile balloons upwards as the sun rises, inflating into the peraderi's massive body. The peraderi remains stationary for ten to thirteen minutes following inflation before it begins its actions.

During daylight, the peraderi's disposition is content, with inclinations towards towards joviality. A social stranger, the peraderi exhibits caring behaviours towards its companions. Individuals stand side-by-side, touch each others limbs, or run alongside or after one another, their lightweight bodies leaving loose indentations upon the sands. When the peraderi moves, it does so with graceful but unsteady steps, swaying in the wind, but rarely toppling.

When not engaging in play behaviours, the peraderi spends its days staring outward at the sea, preferring to face away from large population centers.

Weather conditions also have an effect on the peraderi's disposition. Peraderi during cloudy weather are a bit more listless, but take on an turbulent, more aggressive nature during rain or heavy winds (attempts at individualism once the wind pushes away those layers upon layers of instinctual pretense), defying its typical grouping tendencies and displaying aggressive or territorial behaviours. Fights between peraderi are more showy than they are vicious, with much slapping of heads, flailing of arms, and shoulder-ramming.

The peraderi's presence may have a negative impact upon local marine life,^ᵯ causing fish or other like animals to hemorrhage between their scales, and invertebrates to dissolve in structure and die en masse. Air and land animals, however, display no such ill-effects.^Ꮴ

Just as it displays social inclinations within its strain, so too does the peraderi engage in "play" behaviours with sensitives, as well. It allows itself to be chased, but is not evasive, and returns to the sensitive once the sensitive stops running.

If the peraderi is attacked by a sensitive, it grows more fearful towards stimulus in general (shying away even from distant clanging or sirens), and will avoid all sensitives from that point on.

The peraderi creates a feeling associated with childhood, eliciting curiosity, playfulness, a decrease in anxiety, and a sense of novelty about the world. Even when a sensitive encounters a peraderi for the first time, this stranger tends to be perceived as familiar; a minority of sensitives also experience the feeling that the remainder of the world is out-of-place. The peraderi's effects towards sensitives are most pronounced at the beginning of the day, and particularly on sunny weather.

While the peraderi is tolerant to individual sensitives, larger groups of sensitives have a detrimental effect on the stranger's physical form, causing staining, uncoordinated movements, and fatal crumpling. Behaviour and effects remain unaltered.

As the day drags on, so too does the peraderi's reaction to the world. Its curiosity gives way to fearfulness, and its aggression becomes pronounced. As the sky begins to darken, the peraderi's aggression turns upon itself as it claws at its face, fingertips too weak to pierce its own skin, or pounds its head against the ground, its frame too flexible to be broken by such impacts. The peraderi dies with a crumbling exhalation, and always just before sundown, its corpse shriveling to nothing as the last light sinks beneath the horizon, all fragments drifting toward the sea, blown by unfelt winds.