Ao Gennai mistakenly opens a package that wasn't meant for her, and, to her surprise, she sees a small robot named Gourai, a Frame Arms Girl who has an evolving personality. Confused as to how this little robot made it into her life, she finds out that she is the first person to activate her. She realizes taking care of Gourai is harder than she thought, especially when competitive fights are involved!
Ao opens a package and finds a Frame Arm Girl nestled inside. Afterward, she gets an unexpected visit.
Ao starts to get to know more about the Frame Arms Girls and their functions. Meanwhile, Gourai has other plans on what to teach.
Base goes with Ao to school and certain things start to go missing. Meanwhile, the Materia sisters arrive at Ao’s doorstep.
Ao is trying to teach the girls human manners, but everything is upended when Jinrai arrives and challenges Gourai to a duel.