After failing his college entrance exams twice, Minato Sahashi is flattened by Musubi, a girl who drops out of the sky onto him. She is a Sekirei, one of 108 superpowered beings released into Tokyo by the pharmaceutical conglomerate MBI. Each one must bond with a human Ashikabi through a kiss to unlock her full power, then fight the rest in a battle royale called the Sekirei Plan. Minato becomes Musubi's Ashikabi and soon has more Sekirei in his apartment, among them the water-wielding Tsukiumi and the cloth fighter Uzume, while MBI's chairman Minaka Hiroto forces the game forward.