Junkyard Cleavage
People refer to a woman's ample backside as her having "junk in the trunk". And when a woman's top is low-cut, you can see her cleavage. Combine the two, and you have Junkyard Cleavage, which is also an advertisement..."See this? I got a messy kitchen! Come and see for yourself."
When a woman has the low-rise pants and either A) the lower-lumbar tattoo, or B) the thong, or hey...maybe both, she's showing off her Junkyard Cleavage.