Do you know ghouls from goblins and ghosts?
c.1300, "indeterminate person," from some + body. Meaning "important person, person of consequence" is from 1560s. Somebody else is from 1640s; meaning "romantic rival" is from 1911.
A consequential person: Leroy was a somebody/ I could have been somebody, Charley. I could have been a contender (1566+)