Green’s Dictionary of Slang

sado-masochism; also as adj.

1965		Guild Dict. Homosexual Terms 40: sadie-maisie (n.): Sadism and Masochism.
1979		F. Norman Too Many Crooks Spoil the Caper 115: At night it became a den of vice thronged with venereal short-time hookers, black-leather-jacketed, sadie-maisie, ginger beers.
1986–7		Maledicta IX 162: [heading] sadie and maisie.
2003		K. Cage Gayle 93/1: Sadie adj. (abbr.) and n. • adj. (abbr.) sadistic • n. sadist.