Green’s Dictionary of Slang

this is protected by the red, the black and the green (with a key) phr.

[the colours of black nationalism; play on the minatory signs that indicate a building’s security system]
(US black teen)

keep out, this is none of your business; spec. to non-blacks, this is for blacks only, you couldn’t understand; optionally ext. by sisseeeee, i.e. sissy n. (1)

X-Clan ‘Funkin’ Lesson’ 🎵 on To the East Blackwards [album] Professor X: ‘Freedom or death, we shall all be moved. Vanglorious! This is protected by the red, the black, and the green, with a key, sissssiiiiieeeeeeeees!’.