Otherworldly spaces known as "demon cities" appeared in various parts of Japan, and those who partook in the "peaches" growing there gained unique abilities-but only if they're girls. One day, a down-in-the-dumps high school boy named Yuuki Wagura suddenly gets lost at the entrance of a demon city. There, he meets Kyoka Uzen, the beautiful leader of the seven programs of "Magical Defense Corps," whoo orders him to become her slave?!