basically, it's another reference to a May-December romance where the woman is quite a bit older than the man. This is also referred to a "Mrs. Robinson" love affair, because of the movie "The Graduate" where Dustin Hoffman's character falls in love with his girlfriend's mother.
The love affair and shacking up of Cindy, 54 and Steve, 28 is a classic case of "her Motown, you Motley Crue ".

by I Saw U2 Live Twice March 5, 2007
Get the her Motown, you Motley Crue mug.
Sticking your fingers up someone's butt through their underwear
We were making out and all of a sudden she gave me a motown wedgie!
by BloJSimpson March 17, 2018
Get the motown wedgie mug.