Most likely refers to the name of a STREET located in the Watts section of Los Angeles and is also the birthplace and main residence of the infamous Grape Street Watts Crips.
The Grape Street Watts Crips are known to wear both blue and purple and have an intense rivalry with the Bounty Hunter Bloods and the PJ Watts Crips since 2000 when their 1992 truce with the Bounty Hunter Bloods disintegrated. The Bounty Hunter Bloods later allied with the PJ Watts Crips to counter the Grape Street Watts Crips.
Their name may seem comical but their approach is both ruthless and merciless to anyone who crosses their path or enters their territory without permission.
Stranger: Grape Street? HA! These guys have the names of clowns.
GSWC: You think so?! *POW* *POW* *POW* What do you think now?!