I have a theory: Chousoku Henkei Gyrozetter actually takes place in the same world as The iDOLM@STER many years into the future. I’m going to lay out my ideas for how this transition comes about while also providing ironclad proof of their shared universe.
1) Inaba Rinne is a Futami Descendant
It’s not clear which of the Futami twins Rinne is descended from, but most likely it’s Mami. It’s not clear just how many generations into the future Rinne is removed from Ami and Mami, but Futami genetics are undeniably strong.
The resemblance is uncanny.
2) The Success of 765 Pro and the Start of the AI Car Boom
Thanks to a combination of talent, spirit, and camaraderie, 765 Productions becomes wildly successful. At first, they do only promotions for car companies, but thanks to rich girl Minase Iori’s connections and the advancement of technology 765 Pro manages to start their own automobile line. They name the car company offshoot “Arcadia,” modifying their logo along the way.
Assistants to the CEO continue to dress in black suits in honor of Akizuki Ritsuko.
3) Shijou Takane is Responsible for the Rosettagraphy
At first glance, the Rosettagraphy makes no sense. A mysterious stone tablet that tells humanity how to build advanced cars that turn into robots? It sounds like nonsense, until you remember that Takane is equally engimatic, and that she is capable of speaking in many tongues. As we can clearly tell now, it’s because she holds the secrets of not only technological growth but also of prophecy. If she had revealed it to humanity too soon, who knows what would’ve happened?
Takane was a Messenger in Many Ways.
4) Gyrozetter AIs are Actually Based on 765 Idols
How else would you explain this?
I rest my case.
Laughs were had and joke was milked for all it was worth.