The story follows Issei Hyōdō, a dim-witted, lecherous second-year high school student who is killed by a girl on his first date ever. Issei is reincarnated as a devil, and from that day forward, he serves as an underling of Riasu, a high-level devil who is also the prettiest girl on Issei's campus.
Haruhi is a poor tomboyish student at a school for the ultra-wealthy, able to attend because of a scholarship, and unable to even afford a uniform. One day, she stumbles across the decidedly peculiar but very popular Ouran Host Club. She tries to leave, but accidentally breaks a vase, and unable to pay for it, she's told that she'll have to stay and do odd jobs. That is, until they decide she would be more valuable as a club member. Not realizing she's female due to her appearance, they fix her up and give her a male uniform. She's an instant hit, so they decide to have her keep up the charade even after they find out the truth. Haruhi, being average almost to a fault, doesn't know what to make of the unconventional activities of the Host Club (or of the even more unconventional members), but having little choice, she plays along. Before long, real bonds are formed, friends made, and Haruhi finds herself accepted in a way she could never have been otherwise in this affluent school.
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 it's about to bring pain and suffering to those who love and care for their Sekireis.