It looks like a bug, but it is a parasite. So it is not really an animal. It is more like an insect who feeds off of humans.
"The head louse (Pediculus humanus capitis) is an obligate ectoparasite of humans. Head lice are wingless insects spending their entire life on human scalp and feeding exclusively on human blood. Humans are the only known host of this specific parasite, but many other species of lice are known which infest most orders of mammals and also birds.
A more distantly-related species of louse, the pubic or crab louse (Pthirus pubis), also infests humans. Lice infestation of any part of the body is known as pediculosis.
Head louse differ from other hematophagic ectoparasites such as the flea in that lice spend their entire life cycle on a host. Head lice cannot fly, and their short stumpy legs render them incapable of jumping, or even walking efficiently on flat surfaces.
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