"Let me ask you. Did you know? Ah, I should not be so coy. It was I who taught 'Wallace everything there is to know about Pokémon. Once, I had given up my position as the Gym Leader. In my place, I had entrusted Wallace with the gym. However, a compelling reason arose for me to make a comeback. Ah, but enough chatter. Let us begin our match, shall we? Please, you shall bear witness to our artistry. A grand illusion of water sculpted by Pokémon and myself!"
Juan is quite the celebrity type in Sootopolis, putting on shows with his Pokémon. He has many female fans, and is considered very dashing. In addition to being a Gym Leader, he is a former winner of the Grand Festival. He appeared in The Great Eight Fate and Eight Ain't Enough when he battled Ash, who won the Rain Badge after a tough battle. He has a butler, Sebastian, who also serves as the Sootopolis Gym assistant. Juan uses unique rules in his Gym matches: the first round is a double battle held in a large swimming pool, while the other rounds are held in a battlefield that resembles a lake surrounded by land. Juan also makes a cameo appearance in a flashback in Playing The Leveling Field!.
Pokémon Adventures Manga
Ruby and Sapphire Chapter
He helped train Ruby and Sapphire with the two orbs on mirage island. And afterwards he took his position as Gym Leader again when Wallace took the champion title for the region because of the calamities. He watches the fight in Mirage Island and is surprised that Ruby has a Celebi, he states that the reason why there was a time problem in Mirage Island is because Ruby had the time traveling Pokémon Celebi.