After all, Pisces is the only water sign that doesn’t have armor for boundaries. (They’re represented by fish, whereas Scorpio is a scorpion and Cancer, a crab). And not only that, but Pisces is ruled by Neptune. Neptune is quite literally the planet of illusion, dreams, and fantasies. In other words, it’s all too easy to manipulate a Pisces if they haven’t realized how impressionable they are.