Louse (specifically likely a Head Louse)

Exclusively on the human scalp, attaching eggs (nits) to hair shafts close to the scalp for warmth.

Obligate blood-feeders; they consume small amounts of human blood several times a day.

They are wingless and cannot jump or fly; they move by crawling. They are highly contagious through direct head-to-head contact and have a life cycle of about 30 days.

Risks include intense itching (pruritus) due to an allergic reaction to their saliva and potential secondary bacterial skin infections from scratching. They are considered a nuisance pest rather than a vector for major diseases. There are no known ecological benefits.