First things first, we need to define all melee enemies.
Here's the list of every melee enemy in the game:


Razors, found in the bathroom:





Bottles, found in the Living Room:





Wrenches, found in the Garage:





Garden Sheers, found in the Garden:










The Garden Spade is NOT a melee weapon that is eligible.







Now upon finding a cluster of melee enemies, kill all of them but leave one on screen. [bThe ]Bread Maker is best for this scenario.[/b]

Once it is just you and the one enemy, circle around the screen and avoid having it touch you. After 30 seconds, you will unlock: