This brilliantly purple fruit thrives in northern Japan, in the Tohoku area, but only briefly, making an appearance for about two weeks in early autumn. It grows on a wild vine and, for many Japanese people, is a symbol of the changing seasons. When the fruit is ripe and ready to eat, it pops open on one end. The gooey pulp inside is slightly sweet, while the rind is slightly bitter and is usually used as a vegetable. Do as locals do, and slurp up the flesh along with the seeds.