De:vadasy

Life sucks for Hibiki. Intergalactic society has broken into civil war between males and females; he's stuck on the assembly line for war mecha, relentlessly teased by his co-workers and unable to pursue his dreams of building his own mecha one day. He finally decides he's had enough though, and attempts to break in and steal a mech for his own purposes; this turns out to be a bad idea, thrusting him into the middle of a fever-pitch space battle that brings him face to face with the enemy and launches him into an adventure that will change his mundane life forever.

Hero was a high schooler living an ordinary life. One day, he meets a very strong and intelligent mechanical arm named "Mecha-ude". After a strange turn of events, the "Mecha-ude" started living inside Hero's hoodie and the two's life full of trouble begins. As the boy and his "Mecha-ude" fights together and strengthen their bonds, the two also meets new friends who also fights along with each of their own unique "Mecha-ude" partners. Out of those, one of the heroine has two "Mecha-ude" which appears out of her skirt. An active girl with a totally opposite characteristics from hero himself, he gradually becomes attracted to her. But the two are confronted with other "Mecha-ude" users who are in search of the secret of "Mecha-ude" relentlessly.

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.

In the near future, Earth is at war with aliens called Worms. The war leaves the population of Earth decimated, with young men the main casualties. The Worms were beaten back but their re-emergence heralds the creation of a mecha unit called the Sonic Divers, piloted by 3 young girls to counter this threat.