If playing as Calem, the player character may earn the title of Grand Duke by defeating most of the Trainers in the Battle Chateau. This is the only time the Trainer class Grand Duke appears in game.
Calem is a young boy who lives in Vaniville Town when the protagonist moves into town. Calem is the main rival of the character, choosing the starter Pokémon which is super-effective to the player's. He is also the character who teaches the player and Shauna how to catch a Pokémon, catching a Bunnelby with the use of his Fletchling. Soon after, he can be seen in Santalune Forest with the other friends.
Calem is the child of two prominent Pokémon battlers, and is seen as one of the two best battlers of the group of friends, alongside the protagonist.
The next time Calem battles the player is in front of the Coumarine Gym.
When the group of friends meets up and decides to go to the haunted area in Route 14, Calem is the only one of the friends to not go to the house, claiming that he has to train. He then helps the player defeat Team Flare at the Poké Ball Factory.
The next time Calem battles the player is in front of the Anistar Gym. After the player defeats the gym, he will ask for a rematch, but cancels his challenge after Lysandre announces his plan of eradicating all life forms not a part of Team Flare. He then helps the player defeat Team Flare get to the legendary Pokémon and defeat Team Flare for good.
After the player enters the Hall of Fame and battles at the Battle Maison, Calem can be battled in Kiloude City, at which point he has obtained a Mega Ring of his own. When defeated for the first time here, he will give the player an Absolite and tell the player to meet Professor Sycamore in Anistar City. He can be battled at Kiloude City once per day.
Pokémon
Catching tutorial
Calem has another Pokémon besides his Fletchling, likely his starter, as noted by having two party slots filled during the tutorial.