Drain Deimos are mutated insects that appear as enemies in Resident Evil 3: Nemesis and its 2020 remake. These grotesque monsters were originally common fleas that contracted the T-virus by feeding on the blood of other infected creatures. In response to the infection, the fleas rapidly grew in size, becoming as large as an average human adult.
The Drain Deimos is horrendously disfigured, possessing multi-jointed, awkwardly proportioned limbs ending in sickle-shaped claws. Their bodies are covered in insectoid chitin, but the chitin is cracked and torn in various places, exposing patches of muscle tissue.
Drain Deimos usually move quite slowly unless there is prey in the immediate area. Their claws allow them to crawl along walls and ceilings, though when they encounter prey they will drop to the ground, get up on their rear legs and 'run' at the potential victim. Their wickedly-sharp claws can rend humans to pieces very quickly and the creatures feed by biting open the victim's skull and draining the cerebra-spinal fluid.
In the Resident Evil 3 remake, Jill Valentine encountered Drain Deimos at an electrical substation which they had turned into a hive. The creatures appeared to be shorter and weaker than in the original RE3, though they also had an insidious new means of attacking prey; they would ambush unsuspecting victims and force a proboscis down the victim's throat, implanting them with parasitic offsping that would eventually tear their way out of the host's abdomen. Consuming green herbs would boost the host's immune system and allow them to regurgitate the parasites.
Drain Deimos were quick and nimble, but not very resilient and could be killed with just two or three handgun shots. Their bodies would rapidly disintegrate upon death.