Well, if guitarists name their axes fancy names such as Lucille, why shouldn't we do the same with our basses? I started giving names to my bass guitars, but after the fourth purchase things got silly (I now have 10, plus 2 uprights). So now I simply describe them (the fretless Corvette 5, the Bass Collection, the Fortress 5, etc.).
My first upright is still called Andy (don't ask).
I have always thought of my basses as male - probably because the name is masculine in Italian; they say 'il basso', not 'la chitarra bassa'. (Italian has no neuter gender.)