The alien that lives inside of Konstantin chose him because it could sense that the other member aboard the Orbit-4 had a terminal illness, and that Konstantin was therefore the better host. Very quickly, it succeeded in "establishing a bond" with Konstantin, such that attempts to remove the alien from his body cause his vitals to deteriorate rapidly; he will die without it, and it will die without him.

Essentially, Konstantin functions as a "spacesuit" for the creature "against a hostile world". Whether its contact with the Orbit-4 and subsequent landing on Earth was intentional or a mistake, the creature uses him as a safe home in which to incubate, grow stronger, and learn more about its new environment.

While incubating, the creature takes up 30 centimeters (11.8 inches) and appears as a simple worm or snakelike creature. It stays inside of him for the most part, emerging only at night to feed, slithering up out of his mouth. When it needs to exit his body, it releases a toxin that causes a seizure-like reaction in its host, ultimately relaxing Konstantin's muscles by force and knocking him out. It also produces a membrane so that it doesn't harm his esophagus and throat when entering or exiting them.


^ the creature's size when inside of his stomach.... Big Worm,

Though the creature is much smaller when inside of Konstantin's body, it can expand from its simple, wormlike, tubular form to 1.5 meters in length, once it emerges from its host and ingests oxygen. Once outside of him, it shifts into something more detailed, with long, slender arms which it uses to pull itself around with, and the rest of its body forming a long tail, sometimes with little vestigial back legs that tend to drag the ground or stay pressed to its body. Its more intricate state appears like some amalgamation of creatures: a hooded head like a cobra, a cluster of eyes like a spider, a tail that exudes slime like a slug, a mouth lined with sharp little teeth and held like a sucker (much like a lamprey), though they extend longer when the creature attacks. It is only capable of residing outside of him for about an hour, and after feeding or exploring, shrinks back down and returns to Konstantin's body to sleep and incubate in his stomach.

In all aspects, the creature is incredibly sensitive to the environment outside of it. Its body is soft, squishy, and weak, with a poor resistance to the sunlight. Any abrasive external stimuli such as bright lights, flashing, etc. can cause it discomfort and even pain. Its sensitivity also means, however, that it shows an incredible capacity for adaptability, both mentally and physically.


^ the alien once it has inhaled oxygen and temporarily grown from its small and simple snakelike state to something bigger and more complex


^ another of the alien.... crawling its way to go kill and eat someone

The alien essentially feeds on cortisol — a hormone produced in response to stress and fear. For this reason, it's important that it reveal itself to its victims in order to trigger a release of terror. It stalks and frightens victims just long enough for the hormone to be released into their bloodstream, before going in for a very quick and violent kill, often ripping into the heads / brains of its victims. From there, it feeds on their blood.

While the creature can feed on any animal that produces cortisol, its condition (and therefore Konstantin's) is much more stabilised after feeding from humans.

The alien's relationship to Konstantin is symbiotic. They cannot survive without one another, and mutually benefit each other. As mentioned, Konstantin serves as its literal home and safe environment on a foreign planet, and a means through which the alien is able to learn and adapt. In return, it gives him a "phenomenal capacity for regeneration", meaning that Konstantin can physically heal from even severe wounds at a rapid pace, as long as the creature is within him. His physical performance has also improved even further, making him at the prime of his human capacity.

The creature and Konstantin are also tied in deeper ways. While he's generally unconscious while it's outside of his body, when it returns to him and he wakes later, he has every memory of its experience in minute detail. An unexpected effect is also that the creature retains some memory or sensation of Konstantin's hormonal fluctuations, in the form of being receptive / less hostile / controllable by those he has felt especial fondness to or has strong positive feelings towards, more aggressive or agitated towards those who have frightened or upset him, etc. It also seems to have affection (whether genuine or a mimicry) for the things he does, such as certain items that mean something to its host.


^ the alien hugging the little doll that brought Konstantin comfort up in space