Green’s Dictionary of Slang

(S.Afr. prison) an aggressive prison homosexual; also attrib.

2005		A. Lovejoy Acid Alex 122: The other ouens were doing it too and that made sick fucking nongie thoughts try and get into your head. [Ibid.] 132: Are you a nongie or are you a Das.
2008		A. Lovejoy ‘The Smell of Tears’ at www.acidalex.com 🌐 3: It has been a long time since he was a crying little laaitie pop to be raped and naaied [...] by all or any nongies.