Green’s Dictionary of Slang

rufus n.

[Lat. rufus, red]

1. the female genitals.

[UK]Farmer & Henley Sl. and Its Analogues.

2. a red-head.

[Aus]Bell’s Life in Sydney 27 Sept. 3/1: Peter Brenan, a carotty-headed brickmaker [...] First blood claimed for Rufus.

3. (US) a country person, a peasant [the ‘rustic’ name].

[US]H. Hapgood Autobiog. of a Thief 82: When these Rufus’s up the State get a Yorker or a wise guy, they’ll strip him down to his socks.
[US]University Missourian (Columbia, MO) 7 Nov. 2/1: Some rustic Rufus mau have thus deserted his plow [...] in a fit of despondency.