I think if Marge became an egirl gamer, Homer would be very supportive of her new business. He'd also probably sell beer bottles of her bathwater without asking first, though. Then Marge would realize that there was an inescapable sexual element to what she thought was a wholesome time playing video games while receiving encouragement and support from an audience of fellow videogame enthusiasts. Only after Moe getting sick from drinking bathwater and closing his tavern while he recovers would Homer learn that there were consequences to his merchandising scheme.
The B-plot would be about Bart and Lisa getting into the world of... oh, let's say... competitive geocaching.