Rui was a worker under SUNGUNDAM Incorporation, working in all three main departments, coding, building and designing. He was 25 years old. Rui was a carefree man, who always has his fair share of eccentric ideas for Gundams that he likes to share with his co-workers, despite having a chronic illness that prevents him from properly piloting one, he was also caring yet teasing towards people he considered as family being his mother, the old Kusanagi couple and their daughter Nene, who he especially grew attached to despite interacting a few times. His co-workers had mixed feelings about him, while he was quite smart and prodigious, they think he's a maniacal weirdo due to his high-risk ideas that might put pilots in danger, causing him to distance himself from his co-workers as time goes on and starts to work alone. He also didn't have a good track record of taking care of himself, often forgetting meals which was how he met and befriended the Kusanagis in the first place. He unfortunately passed away, yet his soul seemed to clung into the same suit he built for Nene, making him possess and becoming the suit itself.

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Tomusaku - Toh-Mu-Sah-Ku