Blue Seed (stylized as BLUE SEED) is a Japanese manga series written and illustrated by Yuzo Takada. The plot is based on the Izumo cycle of Japanese mythology. The main character, Momiji Fujimiya, is a descendant of the mythical Princess Kushinada (奇稲田姫, Kushinada-hime). When Japan is menaced by Aragami (荒神, Aragami, lit. "angry gods") spawned by Yamata no Orochi, Momiji is intended to be sacrificed to appease the Aragami. She instead, however, becomes a member of the Terrestrial Administration Center (TAC), a secret agency charged with fighting them.
ごく普通の中学生のはずであった藤宮紅葉は、奇稲田一族の末裔であり、自らが人柱になることによって「荒神」（あらがみ）と呼ばれる謎の怪物を封印する力を持っていた。紅葉を襲う荒神の出現と彼女を守る草薙護の存在。人柱という運命に迷いながらも紅葉は「国土管理室」のメンバーとなって荒神と闘う決意をする。