Babysitter to bitch (LF Younger Boy)

MC is  babysitting YC at MCs house. YC suggests a game of hide and seek, but instead has other motives, to go through her room. What he finds is a bunch of toys, however not for him. He also finds magazines and artwork of what said toys are for. Or maybe he had found them the last time he had been over and has figured out what they're for. Then he blackmailes her into letting him do whatever he wants with and to her, or else he'll tell his parents and possibly make up lies about her touching him.