Fennekin first appeared in A Battle of Aerial Mobility! as one of the three starter Pokémon new Pokémon Trainers could choose from Professor Sycamore. In A Shockingly Cheeky Friendship!, Serena chose Fennekin as her starter Pokémon. Later in the same episode, Fennekin chased a wild Vespiquen that was about to attack Serena away with Ember, demonstrating courage and care for its Trainer.
In A Blustery Santalune Gym Battle!, Fennekin woke up with Serena at a Pokémon Center and enjoyed a large breakfast with her. Fennekin mimicked Serena's actions during their breakfast by stretching as the same time she did. Later in the same episode, it was introduced to Ash, Pikachu, Clemont, and Bonnie and greeted them happily.
In Giving Chase at the Rhyhorn Race!, Fennekin had its first battle, fighting against Team Rocket and using Ember to blast them off.
In Grooming Furfrou!, Serena left it with what she thought were Pokémon Stylists so it could be groomed. Unfortunately, the "Pokémon Stylists" turned out to be Team Rocket, who were running a scam to steal Pokémon. When Serena saw the "Pokémon Stylists" on a wanted poster, she rushed to rescue Fennekin, and did so with the help of Ash, Pikachu, Jessica and her Furfrou.
In Clemont's Got a Secret!, Fennekin was sent out to battle a Magneton owned by Clemont that was patrolling the Lumiose Gym under orders of Clembot, the robot that had usurped the Gym from Clemont. However, Magneton dodged its Ember attack by separating into three units, but the group was saved by Ash, Pikachu, and Froakie before it could attack Fennekin.