Ootomo is a somewhat tall boy who wears the LID uniform with a black undershirt visible beneath. He has brownish hair in a style similar to an undercut and the longer part of his hair is fixed in a short ponytail.
Pre-Arc League Championship
Ootomo, Kakimoto and Yamabe met up with Sylvio at the LID Center Court when the latter invited the You Show Duel School students over. At Sylvio's request, Yuya let Ootomo and the other two see "Stargazer Magician" and "Timegazer Magician". Sylvio then claimed the cards as his, and challenged Yuya to a duel. On Sylvio's cue, Ootomo grabbed Allie, Frederick and Tate, and held them hostage. Sylvio lost the duel, and ordered his friends to take Yuya's Pendulum Monsters by force, but Sora Perse knocked them out with his lollipop.
A few days later, Ootomo and Yamabe met up with Sylvio inside a warehouse near the port, having bought his favourite food for him. Then, when Zuzu busted the warehouse door open and Sylvio choked on his food, Ootomo handed him a bottle of water. He and Yamabe then witnessed a masked duelist intrude the warehouse and unwittingly challenge Sylvio in Zuzu's place. Sylvio lost the duel and was knocked unconscious; Kakimoto and Yamabe carried Sylvio out of the warehouse, with Ootomo following behind them.  The next day, he, Kakimoto and Yamabe told Gong Strong about the attack on Sylvio, and accused Yuya of committing the attack. This lured out Skip Boyle and Yuya in front of You Show Duel School, with the others following; the three lackeys revealed that Zuzu bore witness to the attack. Eventually, Henrietta Akaba arrived at the school, leading Skip and their students back to LID; Claude stayed behind to give prize cards to Kakimoto, Yamabe and Ootomo for backing their story. 
Arc League Championship
Kakimoto, Yamabe and Ootomo were seen watching Sylvio's rematch with Yuya at the Arc League Championship, and were impressed by Sylvio's new Pendulum Monsters. 
After Z-ARC's defeat and the Standard Dimension being reborn into the "Pendulum Dimension", Ootomo was seen watching Yuya Sakaki's Duel against Jack Atlas with Kakimoto and Yamabe. He cheered when Yuya won and watched Yuya and Declan's Action Duel. He was happy when Yuya won the Duel and witnessed Zuzu's revival.
- ↑ Yu-Gi-Oh! ARC-V episode 3: "Trade Bait: Part 1"
- ↑ Yu-Gi-Oh! ARC-V episode 4: "Trade Bait: Part 2"
- ↑ Yu-Gi-Oh! ARC-V episode 7: "Mr. Mystery"
- ↑ Yu-Gi-Oh! ARC-V episode 8: "Bad Business"
- ↑ Yu-Gi-Oh! ARC-V episode 31: "The Pendulum Swings Both Ways: Part 1"
- ↑ Yu-Gi-Oh! ARC-V episode 146: "One Way Street to Defeat"
- ↑ Yu-Gi-Oh! ARC-V episode 147: "One Last Duel"
- ↑ Yu-Gi-Oh! ARC-V episode 148: "That's a Wrap!"