The merridronel (/mɛrədroʊˈnɛl/) is a small, blue stranger with short limbs and a long, tubular body, which, in conjunction with its wobbling movements, evokes a musteline appearance. The merridronel can be thought of as a kind of animate water balloon, with skin composed of a solid piece of thin, stretchy rubber, and a body filled with watery gel. Due to its wholly contiguous exterior, the merridronel is unable to open its mouth, the lips of which curve upward into a fixed smile. Its toes are similarly fused together.
The humectant substance inside its body disappears when touched, and feels much like glycerine-based gel, eliciting a similar coolness upon the skin.
The merridronel's fragile skin can be popped with any sharp edge, such as a knife or needle, but even a rough scratch of the fingernail is enough to burst the merridronel's fragile form. Heat causes its body to pop and fizzle, although the merridronel does not appear affected by cold, and its inner gel remains fluid even in freezing temperatures. Because of its fragility, the merridronel possesses no regenerative ability.
The merridronel's presence is accompanied by random but melodic musical notes, similar in sound to a jack-in-the-box.
The merridronel can be found in damp or humid interiors of all kinds. Infestations always begin with a single individual, which starts off as a small, rubbery bead that swells to form the mature merridronel within six seconds. Groups spread via duplication, as the initial merridronel and all subsequent individuals split themselves laterally to duplicate in an amoeba-like manner. The rate of this duplication is based upon the number of people nearby, with lower numbers of people causing the merridronel to duplicate at a faster rate. In areas of average city population density, each merridronel duplicates itself once every 50-180 seconds, while merridronel in less populated regions duplicate every 3-10 seconds.
The merridronel cannot grow to completion in overly dry locations, where it instead appears as a moist, crumpled husk upon the ground, which leaves behind the smell of burnt rubber as it dries and crumbles apart.
The merridronel possesses a whimsical and simple disposition. Despite its vulnerable body, it displays little regard for its surroundings, and moves with wobbling, dance-like hops and bounds. Its movements express a perpetual happiness, and its melodic voice contributes to this merry impression.
The merridronel performs no actions beyond its enthusiastic leaps and flops, and does not interact with its surroundings in any deliberate way, although its bouncing can pose a hazard to any easily toppled objects nearby, such as stacks of cans or bottles.
Despite their lack of coordination, groups of merridronel tend to stay close to one another, and do not wander apart or spread themselves too thin. When enclosed in a small enough space, it takes little time for individuals pile up on top of one another, which causes those at the bottom of the pile to pop under the weight of those at the top. As such, groups tend to remain at a stable size once the group covers the floor of the room that they occupy.
The presence of sensitives does not alter a merridronel's actions in any way. When pushed on its side, it rights itself, and it can even be picked up as long as care is taken not to puncture its body. When held, the merridronel continues to move and wiggle, oblivious to its captivity. Those sensitives who wish to spend time with the harmless merridronel, but do not wish to risk popping one by picking it up, may lie down on the floor near an infestation, where they will soon find themselves covered in tumbling piles of joyful merridronel.
Touching a merridronel alters its ability to duplicate itself, resulting in improper duplicates. At first, these duplicates present with only minute differences in proportions, or slight variations in color or skin thickness. Further individuals duplicated from these improper copies display more noticeable deformities, such as missing arms, truncated tails, or frowning mouths. After 3 generations, duplication becomes much more irregular, as merridronel begin to split in a longitudinal manner, or divide into 3-4 small, misshapen individuals. Subsequent generations no longer divide into two individuals, and instead, split apart into two severed halves, which themselves divide into even smaller, twitching chunks. These chunks do not divide any further, but do continue to bob and swell, as though in sync with some invisible band.
Infestations of merridronel are short-lived, and their longevity as a group is contingent upon the initial merridronel's age. Once the group reaches the end of the initial merridronel's lifespan, individuals begin to pop spontaneously, with all members of a group bursting within thirty to seventy seconds. Upon bursting, the merridronel's skin dries up and shrinks to nothing over the course of several hours, while its gelatinous filling evaporates within twelve to nineteen minutes. Copious amounts of the merridronel's gel causes mild discoloration on some papers and fabrics, but otherwise, the merridronel has little impact on its environment.
Infestations often appear in direct succession, in specific locations whose properties support merridronel generation (such as humid locker rooms and damp basements). The gel-like substance left behind by merridronel corpses does not evaporate in the presence of subsequent merridronel, leaving the groups that follow to splash with glee in the remnants of their antecedents.