Summary [AniDB]: * Based on a light novel series by [Yumizuru Izuru], illustrated by [Okiura].
The students at the IS Academy are trained to become pilots for the Infinite Stratos (IS) weapon system. And [Orimura Ichika] is the only male among the otherwise female students at the academy capable of piloting an IS.
Much to the chagrin of the five girls — ojou-sama [Cecilia Alcott], sporty [Charlotte Dunois], girly [Huang LingYin], sober [Laura Bodewig], and tsundere [Shinonono Houki] — that already have a crush on Ichika, other rivals appear...
Such as the mischievous and quite direct student council president [Sarashiki Tatenashi] who forces Ichika into additional "training", to improve his skills in combat. Or a previously unknown little sister, [Orimura Madoka], in cohorts with some enemy force, linked to the worldwide theft of IS units. Or Tatenashi`s shy younger sister [Sarashiki Kanzashi] Ichika is asked to team up with for the upcoming tag matches.
— written by foo2