Your Mom Is Like a Penny

Alright, listen up, you chucklehead. Your mom is being compared to a penny. Pennies have two sides, so calling someone 'two-faced' means they're dishonest. 'Flat' is just saying she ain't got much junk in the trunk. And the 'pants' part? Well, pennies end up in people's pants pockets, and that's a cheeky way of saying she gets around, if you catch my drift.