After a successful operation carried out by an AEGiS attack unit, Nodoka Takahata seeks a job as an Actress, a woman born with the ability to wield mechanical suits.

Nodoka is an avid hiker and wants to climb Mt. Takao with Yotsuyu. On the hike, she meets a long-tailed butterfly but finds something else the girls have never seen before...

Nodoka becomes suspicious when Yotsuyu starts coming home from work early. What’s going on here?