An ass volcano is the act of inserting baking powder, vinegar and red food coloring to a gaping asshole (normal it has been stretched out from a vigorous session of anal sex). Once the ingredients have been inserted you will have a grade 7 caliber explosion that even an all taco bell diet can not top.
Did you hear about that piece of whore trash Justin rammed the other night ? I hear he rammed her right in the ass and gave the cum dumpster a fucking ass volcano. I would makke the whore my wife.