Marplot: A meddlesome person whose activity interferes with the plans of others. As in, "That grandma who poked holes in her son's condoms so that she would get a grandchild is a real marplot!"
I've been sitting on this one for a while, trying to come up with the perfect scenario for a marplot. I didn't want to have to resort to drawing Scott and I watching our ridiculously loud neighbors move out trashbag-by-trashbag and gleefully giving each other the play-by-play from the couch (though that did happen this weekend, and yes we are turning into old marplots—but hey, it's going to be a lot quieter now that they've moved out). Luckily, I remembered this fantastically insane grandma story on Dear Prudence and the day was saved. (Wipes sweat from brow).