Tatsuya is the School President of Izumogakure.
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Born into a prestigious family, it was decided that he would follow his father's footsteps with his life was all devoted to studies, devoid of anime and hobbies. This continued until he was 7 years old when he met Toru, a boy of the same age as him, who brought him into the world of Gunpla Battles. Ten years later, when he was a 12th-grader, he became president of both Seiho Academy's student government and its modeling club. He was also adored by the student population and was extremely talented at Gunpla building and battle; making it all the way to the world championships of the last Gunpla Battle tournament.
Paul Gekko ArcEdit
He is introduced in the White Angel, where he visits Paul Gekko's chamber during lunch time. Tatsuya then asks Paul about how he defeated the Ten-Tails where Paul tells him that he was able to defeat him thanks to his Students. However Sei tells him that Reiji is not interested in Gunpla battles, so he gave up on him. Hearing about Reiji increases Tatsuya's curiosity over him. Then Mira Gekko enters the room, telling Paul that there is trouble, where she points outside, showing Takashi doing a wrestling move on Monta Gonda. After Paul stopping him, Monta asks Tatsuya why he is allowing Takashi to enter the school grounds, where Tatsuya lies to him saying he invited Takashi and Shinka to the school for his piloting abilities, and how he was the one who defeated the Ten-Tails. Monta asks Tatsuya if Reiji can show his abilities, and that he would like to Gunpla battle against him. Tatsuya allows it, where afterwards he becomes the judge of the Gunpla battle between Paul and Takashi's RX-79-9 Banshee Gundam and Monta's MRC-F20 SUMO. During the battle, after seeing Takashi's unique piloting abilities, he becomes fired up. Takashi charges and wins the match. However Tatsuya Yuki challenges to a match in his MS-06R-AB Zaku Amazing, which made the 6th World Championship. Mr. Ral explains that Tatsuya's immense piloting skills had given him the nickname of "The Crimson Comet". Reiji charges into the fight, but the Zaku Amazing manages to dodge Takashi's attacks with its high mobility, and manages to disarm the Banshee Gundam. Paul and Takashi are stunned they were only defeated in seconds. Tatsuya is seen monitoring the school grounds with Monta, where he sees that Sei is busy designing the Build Strike Gundam's new equipment.
- Tatsuya and Tatsuya Yuki is shown like the Prince and the Pauper Story.