Steve Finds the Gun

"Hey, babe? What's this? I just found it in the desk in the living room," Steve says, walking into the kitchen.

You turn away from the kitchen counter, where you're preparing your husband's dinner, and look at what's in Steve's hand. It looks like a toy gun, but at the back of your mind, you have a feeling that it's much much more. In fact, you know it is. Oh no! The stereotype gun! you think, as you remember that you're not Marcy, but rather Mark, Steve's roommate. Your mind then recalls what you've been doing since Steve returned home and feel sick. Unfortunately, you're so focused on your memories of having sex with Steve that you fail to warn him about the Stereotype Gun.

"It looks like a prop for some kind of sci-fi movie, or maybe a child's toy?" Steve says, then he points it and pulls the trigger, not realizing that whoever gets zapped by it would change. But how?