Being born into the world of angels with no wings has always made Shirou stand out. Although many look down on his existence, the spunky 17-year-old is determined to find a way to take flight in spite of his physical handicap. Though he often fails, he continues to refine his mechanical wings in hopes of one day becoming the most powerful angel—known as the Archangel. Shirou's efforts do not go unnoticed as he soon meets a one-winged girl named Eru. Unlike him, she has given up on flying but greatly admires the boy's desperate attempts to soar through the skies. However, when a demon appears and abducts Eru in the process, Shirou finds himself springing into action to rescue her when it seems like no one else can. [Written by MAL Rewrite]