Green’s Dictionary of Slang

sexually voracious.

1888–94		‘Walter’ My Secret Life (1966) II 242: A fresh woman who shivered with delight the instant the prick entered her, who was randy-arsed enough to learn anything in the way of copulation.
1999		D. Lypchuk ‘A dirty little story’ in eye mag. 8 July 🌐 Secretly, though, he was a bit of a happy shopper; a Gillette blade wearing bifocals, which is why he was so randy-assed.