Friend: You live right in middle of the large brown spot!
Source: (Human) Wasteland
My friend had correctly identified that the large brown spot was the Tenderloin, my residential neighbourhood in the land of the free and the home of the brave. The filthy downtown district consists of historical buildings, good nightlife and dining options, and a community of homeless (but not hopeless) people, drug addicts, nutcases who had been released from asylums and left to fend for themselves without any societal support, and other maladjusted individuals.
More loin than tender, I wondered how the area had earned its moniker and did some investigation. It seems the original Tenderloin referred to a seedy section of New York in the 19th century that shared many of the same characteristics as its present day San Francisco namesake.
Dirty cops earned so much money for looking the other way at the sinful activities taking place in their precincts, that they could now afford to eat expensive tenderloin steaks rather than the cheapest hunks of meat that their meagre salaries would otherwise allow for if they had not engaged in graft and bribery. The San Francisco version had borrowed the name as 'the Tenderloin' became a more generic term for crime-infested red light districts across America.