Green’s Dictionary of Slang

sexual petting (and intercourse), esp. in a dark cinema.

1972		‘J. Dark’ Satan’s Victor 178: Bruno’s hands brushed against Victor. ‘You and the feelies!’ Victor murmured. ‘Damn it, Bruno—do your job! You can grope later’ [Simes:DLSS].
1972		‘Rich Cummings’ Suckhappy 102: Johnny grabbed my hand. Fa Chrissake, this was no time for feelsies.
1984		Partridge DSUE (8th edn) 384/2: since 1945.
1989		T. Blacker Fixx 180: Down boy [...] Feelies are for upstairs.
1993		R. Shell Iced 45: To hang out and sneak feelies and kisses with the girlies.
1996		J. Smart Not Quite Straight 11: Aged 5, their daughter Royce Holland and I were relentlessly and shamelessly sexy and we used to have furtive ‘feelies’ [Simes:DLSS].