The town drunk (also called a tavern fool) is a stock character, almost always male, who is drunk more often than sober.
The town drunk typically dwells in a small enough town that he is the only conspicuous alcoholic. Larger cities may have more than one, but this term appears to come from around the 17th century; in the stereotype, when a city grows large enough to house a sufficient mass of town drunks, the area where they congregate becomes known as Skid Row.
In fiction, the town drunk character serves a number of functions.
(Town drunk he's the town drunk
He was once a man of means but just look how low he sunk
The bright lights that glitter led him to the gutter now he's the town drunk)
I know it I know I'm the town drunk but once I had a good life
A fine home and a lovin' wife
Why I was respected by the whole community
Then I got to drinkin' real real bad I lost everything I ever had
I just couldn't control my drinkin' and now my drinkin' it controls me
(Town drunk...
Yeah that's right the bright lights that glitter led me here to this gutter
(Now he's the town drunk)