Ryouta Katou is a Slifer Red student who appears exclusively in Yu-Gi-Oh! GX Spirit Caller.
Ryouta can be found in the areas surrounding the Red Dorm.
He advises the player to explore the different buildings on the island to find more opponents, but feels that he himself loses more easily when he wanders too far from his dormitory.
Ryouta regards the player as the star of Slifer Red and feels privileged to add him as a contact. Soon after, he sends the player the following message:
There are lots of secrets on the island. Like I don't go into the forest at night because it's scary. You shouldn't wander too much around either, so duel somewhere safe.
- Ryouta uses this Deck at the beginning of the game.
- Ryouta uses this Deck once the player has defeated Jinzo.
- Ryouta uses this Deck for the rest of the game once the events involving the Shadow Riders begin.