the.com/creep

means To move slowly and stealthily, or — in slang — a person whose off-putting, furtive manner makes your skin crawl.

from From Old English 'creopan,' meaning to crawl close to the ground, a word with ancient Germanic roots (kin to Dutch 'kruipen' and German 'kriechen'). The crawling sense came first; the 'skin-crawling person' slang emerged much later, by the early 20th century, as English speakers took the physical sensation of something creeping over your skin and pinned it on the people who caused that feeling.