The 12 refers to Boca's fans, some of the best in the world. A visit to La Bombonera is a must for anyone who goes to Buenos Aires
Lyrics
And go, go, dale Boooo, We want (the) Copa, The 12 is crazy wants a championship to celebrate, I'll come to sing you on, as every year, Put your balls into it *Xeneize can not lose... (Repeated...) * Local dialect for people who come from La Boca in Buenos Aires