In Tokyo in the year 2020, Sahashi Minato has failed the college entrance exam twice, is awkward around women, and unemployed. One day, Minato meets a girl named Musubi, who literally falls from the sky.

Minato soon learns that she is one of the Sekirei and he is her Ashikabi, a human with special genes that allows them to form a contract with Sekirei. This binds the Sekirei to him and allows them to use their full power in the Sekirei Plan, a dangerous and deadly competition organised by Hiroto Minaka, chairman and founder of the mysterious and powerful MBI Corporation. Minato finds out that being the partner of a beautiful girl is not all fun and games, especially when he discovers that an Ashikabi can have more than one Sekirei partner — and that’s where the real trouble starts.

The battle to find the supreme Sekirei continues. Still some of the fighters and their masters refuse to participate in the battle since losing it means to lose the Sekirei forever, and many of them actually care about their partners, while others just use them as tools. A storm is rising on the horizon, a bigger threat approaches the city and its about to bring pain and suffering to those who love and care for their Sekireis.