Haha, the same thing just happened to me. My two sims Audrey and Ethan had just got married and later that evening Audrey get this call of a random sim saying "I dialed a random number and you answered, i guess we should get to know each other!" He had invited me to Forgotten Grotto and i was quit intrigued so i went. It was normal for about five minutes but than another random sim shows up and everyone starts vomiting, Mind you Audrey was pregnant but even a pregnant sim wouldn't vomit as much as she did. The thing thats creeped me out the most though was when the townie sim that randomly showed up died and the grim reaper appears in the world. I left straight after because i had the feeling my sim would be next. (I know it has something to do with the slice Of Life Mod) but its still eerie.