Sekirei

Japanese Title: セキレイ

English Title: Wagtail

First Season: Sekirei
Minato Sahashi is extremely intelligent, yet due to his inability to cope under pressure has failed the college entrance exam twice. As a result he has been branded an idiot and loser by many. One day after talking to his yet again disappointed mother he comes into contact with a girl named Musubi who was under attack. The girl runs but takes him with her and soon finds that Minato, while unknown to him, is an Ashikabi, one of the mysterious set of masters that have the genetic trait that can become partners with some of the 108 cute girls, buxom women, and bishōnen called "Sekirei." The reason for the partnership allows the Sekirei to use all their power to win in the competition held by the mysterious MBI corporation.

Second Season: Sekirei: Pure Engagement
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.