Cologne is a fine-smelling liquid that one applies to his body to make him smell better.  It is common in many European countries.  It originated during the black plague in Europe.  They would put cologne and perfume on a kerchief and when they passed a deceased person, they would smell the cologne to cover the other smells nearby.  Now, though, culture has transformed it into a symbol of status.  You smell like you are wearing expensive cologne and people treat you better.  It's all about status.