Green’s Dictionary of Slang

(US Und.) a partner in crime, an accomplice, a friend.

1969		Smith & Gay Heroin in Perspective (1972) 104: A distinction is made between a hustling partner and a crime partner (crimey) [...] however as one informant put it, ‘there are larceny-minded crimeys’.
1989		(con. 1982–6) T. Williams Cocaine Kids (1990) 86: My crimey here thinks the way to go is more drugs. [...] But I know better.
1994		P. Baker Blood Posse 326: He was with one of Rano Dread’s crimeys.
2001		(con. 1975–6) E. Little Steel Toes 110: Sydney was my crimey’s old lady.
2005		Prison Slang Mommyblogger mydogharriet.blogspot.com 23 Sept. 🌐 Maybe that is why she decided to go off the chain and doowop her crimey’s choney.