We've learned a lot about Kobe Bryant in his short time on Twitter. For instance, the Los Angeles Lakers star loves referring to himself as "Mamba." He is also kind of corny and incredibly focused, even to a fault. And thanks to a series of tweets on Monday night, we saw just how torn apart Bryant is by his team's recent losing ways -- and that he has been holding out on us regarding his musical prowess. Who knew the Black Mamba was also the Piano Man? The Lakers lost to the Bulls in Chicago on Monday, their third consecutive defeat and their ninth loss in their past 11 games. Bryant expressed frustration after the game, and later that night…