Me: "Oh don't worry about him. He's got a really bad case of SGS."
San Juan: "Oh..."
a girl who is quite drunk and sloppy (puking, falling, and extreme loudness/slirring of words is consistent with being sloppy); therefore has a "sloppy swag". saying deriving from the saying/song single girl swag which came from pretty boy swag. this however is not a song nor saying but a way of life. :)