look up any word, like b4nny:
 
1.
When one man (or lady with strap-on) has three or more naked women stacked up and willing to take it doggystyle in successive turns by the one man (or lady with strap-on). The result of their positioning, lying on top of one-another, forms a stack of asses known as an ass-stack.
"I had 5 girls, naked and willing, in an ass-stack" he said.
by Beef Nachos January 29, 2014