Infinite Stratos (or IS for short) has quickly become at once the greatest tool and deadliest enemy during world conflicts. Unique for the IS, however, is its limitations: only women are able to pilot them. Enter Ichika Orimura, brother of one of the greatest IS pilots in history, and after coming in contact with an IS at 15, oddly capable of piloting one himself. This strange occurrence opens up new worlds for him, and he is immediately enrolled in a school that specializes in IS pilot training. A school...of just girls. Is this a dream come true, or a nightmare come to life?