While privately photographing your favorite female cosplayer, you restrain her and shove a vibrator coated in aphrodisiac into her vagina, turning it on and leaving it there. The aphrodisiac seeps into her mucous membranes, causing her hips to start moving on their own. Once you touch her body, she'll twitch uncontrollably, and all you have to do is present your rock-hard cock in front of her. Look, she's already started licking it eagerly...
