A notice has been sent to the magic high schools across the country that a portion of the events in the Nine Schools Competition will be changed. Shockingly, three of the six events will be changed. In order to respond to the sudden change in events, First High School's Student Council is thrown in a frenzy to understand the new rules, reselecting athletes and readjusting their CADs. While everyone was complaining about the Competition's management due to the sudden change in timing, one month before the start of the Nine Schools Competition, Tatsuya had a growing suspicion about the strong military flavor of all the newly added events.

It turns out that the secret experiments that the Kudou Family has been conducting was for developing parasite dolls, a female combat robot possessed by a parasite. Experiments on the dolls' operations are being conducted at the Steeplechase Cross-country venue, where security is abnormally tight - so much so that Tatsuya himself can't even break into the premises. As such, Tatsuya orders Pixie to keep an eye out for the parasites while he conducts adjustments to the CADs and gives instructions to the underclassmen as an engineer. However, this continual sense of nervousness and nonstop days of hard work are tiring out Tatsuya. He's never felt this tired before.