Green’s Dictionary of Slang

cunnikin n.

also cuntkin, cuntlet
[dimin. of cunny n. (1), ult. cunt n. (1)]

the vagina.

[UK]Farmer & Henley Sl. and Its Analogues.
[UK]Farmer Vocabula Amatoria (1966) 75: Connaud, m. The female pudendum; specifically that of a young girl; ‘a cuntlet’.