Which begs the question of the effects of that leaked gravity in the other dimensions. It also makes for interesting thought experiments on the possibilities of increasing or reducing said leakage.
It's not really leaking into another parallel world. It's just having its effect in more than the three spatial dimensions. Since the extra spatial dimensions are coiled up tight, the gravity effect is more or less lost there in a dimension we cannot interact with.
My perpetual motion machine uses duct tape -- lots of it -- to minimize the leakage. Very soon now, I shall astound the world!