A blonde suspects that her boyfriend is cheating on her, so she goes out and buys a gun. She goes to his apartment that same day, with the gun in hand.

Sure enough, when she opens the door, she finds her boyfriend in the arms of a redhead. She points the gun at her boyfriend and stares him down for a moment.

Then, suddenly, she's overcome with grief, so she puts the gun up to the side her head. The redhead yells, "Wait!  Don't do it..."

The blonde yells back, "Shut up! You're next!"