[F4GM]looking for a gm for a sci fi/mechs and kaijus themed rp

I'm 18+ and all characters are 18+

greetings, I am looking for a gm for a concept that I have in mind for a sci fi theme rp, as mentioned in the title.

in regards to the system, I know a simple and with room for modifications which we could use, alternatively if you like to use a different system, we can try it out.

here's the premise:

In the distant future, mankind had begun to venture into the wide galaxy, laying claim to and colonizing habitable worlds. However, as humans plunged deeper into the wider galaxy, they discovered gigantic-sized lifeforms which they labelled as kaijus. Using advanced mechs, they battled against the kaijus but struggled to overcome the kaiju’s immense power. Thus, a new approach was sought after. Instead of humans fighting the kaijus personally with technology that struggled to best them, they’d have these colossal beings fight against each other, discovering some kaiju species were somewhat docile to human control. 

Using experimental mutagens, humans injected these docile kaiju with a substance that modified their DNA in the hopes that further generations of these kaiju would be more obedient and more open to being trained as an effective fighting force. These results varied, for better or worse, but it was worth it. Then, after several generations, these kaijs would lay eggs that gave rise to an unexpected result. From these eggs, human-like kaiju were born, resembling the average-sized human with subtle traits of their parents and fully capable speech and human-level intelligence. Yet, they also possessed the ability to grow to the size of and transform into mighty kaiju, while still maintaining their human mind. 

The government keeps these individuals secret from the general public. As far as the population understood, these special kaiju were nothing more than well-trained monsters in service to humanity. These individuals would be kept within hidden facilities, only being deployed when an objective needs to be met for the sake of all humankind.