In the first episode of Once In A Lifetime, a lewd adventuresque VN from Caribdis, we are introduced to Percy, a rather ordinary guy living a rather ordinary life with his parents and his two... sisters - a life that typically values having fun over putting in the effort, much as our hero would like to turn this around. The story properly begins when the parents take a trip out of town, leaving Lauren and Judie in charge of the house and, as it happens, also in charge of coaching Percy in the school subjects which he is failing (incidentally, that's pretty much everything). It might all have gone smoothly enough, had Lauren not had the (mis)fortune of catching her brother sleeping in the nude... well, he might be failing in his studies, but he's definitely succeeding in something else!