Green’s Dictionary of Slang

that there n.

the vagina .

1984

Partridge DSUE (8th edn) 1215/2: C.20.

In phrases

a bit of that there (n.)

any form of sexual embrace, up to intercourse.

1883		‘Three Chums’ in Boudoir I 4: They slip into ours for a drop of brandy and a 'bit of that, as they call it.
1894		Mirror of Life 24 Mar. 7/3: Whilst he had one of his favourites in tender embrace [...] imprinting a kiss on her lips, one of the lads bobbed his head up and shouted, Hi there, mate, I’ll ’ave a bit of that’.
1984		Partridge DSUE (8th edn) 1215/2: C.20.