How do I buy from the toy merchant without having my game suddenly ended!? To my knowledge, it is the only merchant that has sex toys, but I need to be adorned with sex toys to avoid the game over???

From what i remember its if you have every toy slot full when you visit her that you get the game over. So even if its unintended you still going to her fully adorned in toys shows your willing to do the scene and choice in the game over. If that makes sense.