"Clean Up on Aisle Four" is a song sung by Marty aka the Huge Fro Guy in the episode "Josh's Sister is Getting Married".
Marty: This goes out to a young lady currently restocking feminine products. It's called "Clean Up on Aisle 4." Not an actual clean up, Rick.
Clean up my heart on aisle four
'Cause that's where lays in a heap of green olives from the olive bar
'Cause I'm the pimento to your olive
I wanna be inside of you
But instead my heart is on the floor
Being crushed like the garlic we sell by the door