Clemont is the Gym Leader of Lumiose City and, with his sister Bonnie, met Ash when the gym mechanisms malfunctioned and almost killed Ash. He seemed very caring towards his sister. He is known for making numerous inventions including the Aipom Arm on his back. He joins Ash after the Lumiose Gym at Prism Tower gets damaged, but Ash didn't know his true vocation until they returned to Lumiose City. He has left the gym under the control of a robot her created, but has promised to battle Ash himself when he has four badges.
For the list of Clemont's Pokémon click here.