From the introduction: Welcome to Shin Tokyo, a bustling urban metropolis and chosen location of the soon-to-begin Sekirei Game. Unlike chess or card games this is a considerably more dangerous activity, a battle royale between 108 beings known as Sekirei and their chosen human partners, all aiming to be the last pair standing. The reward for all your hard work will be to fly in the sky with your flock of wagtails.