to further elaborate on the "porch monkey" phenomenon, a "stoop nigga" is someone who's broke ass can't stay at they mama's house no more, so mama kicks him out..he can't take nothing with him because he ain't got shit..so he go for a walk but realizes before too long he ain't got no where to go and no where to stay and no car/bicycle/roller skates, etc, to get him there, so he go back to mama's house..but since he got "pride" (or something) he don't go back inside since he been kicked out..so he just sits on the stoop, hoping someone will let him back in.
"that nigga low. he a stoop nigga."
"goddamn that nigga 25 years old and he still sleepin all day at mama's house, eatin' reese's puffs cereal at 4pm when he wake up, stay up all night playin video games and shit. his mama need to throw him out, make that nigga a stoop nigga."