What's the thing with can opener?

I am re-watching suits i can't help but wonder what's the deal with can opener

In the Harvey and Donna origin episode Harvey chooses this can opener as per trial ritual but exactly they do with it ?

It can't be anything sexual because when both Harvey and mike were high and they came to office to pee all over but Harvey says it's not right and they went back to get the can opener

I would love to hear the thoughts and theories of what you all think what it stands for