Prior to the start of the X & Y arc, Y took Fletchy to the Vaniville Town Sky Trainer academy. Due to being jealous of her mother's status as a Rhyhorn racer, Y was picked on by her classmates repeatedly. One of the things she was mocked for was choosing to take Fletchy, who was a Fletchling at the time, to school despite her being ineligible for Sky Battles.
Fletchy debuted as a Fletchling in An X-cuse to Come Out and Play, where she was seen flying to X's house alongside Y in an attempt to get X out of his house. In the next chapter, Fletchy escaped Vaniville Town alongside her Trainer to escape the destruction caused by Xerneas and Yveltal battling each other.
In Inn-teresting Developments, Y and Fletchy battled the Team Flare member that trapped them inside an Aquacorde Town inn. When Y noticed that X was in trouble outside, she attempted to open the window to help him but was unable to. Seeing this, Fletchy smashes the window with her beak, allowing Y to break through to get to X.
In Overthrowing a Tyrunt, Fletchy battled alongside Croaky, Tierno's Corphish, and Shauna's Skitty against Team Flare Grunt's four Espurr. Due to learning that her mother was kidnapped by Team Flare, Y became distracted, which gave the Espurr an advantage in the battle. The Espurr were later defeated when Cassius arrived and used his Gourgeist to confuse them. After the group was taken to Cassius's house, Fletchy looked at her Trainer sadly when she noticed that Y had become depressed from the knowledge of her mother's fate.
In Burning Fletchinder, Fletchy battled Yvette, a former classmate of Y's that had been put under mind control along with other Sky Trainers. During the battle, Yvette repeatedly taunts and mocks Y by insulting her mother. This action angers Y into defending her mother, which helped get her out of her depression. Now calmed down, Y's passion for defeating Yvette helped Fletchy to evolve into Fletchinder, giving her the strength to defeat Yvette's Vivillon. With X defeating the Aegislash that put the Sky Trainers under mind control, Yvette passes out, forcing Fletchy to catch her and lift her to safety.
In Pinsir Changes, Fletchy flew Y around to chase Essentia through the skies of Anistar City after discovering that she was behind the attack on Professor Sycamore. After chasing Essentia down a corner, Essentia's Hawlucha appears and hits Fletchy with a barrage of pointed stones, knocking her out. Fletchy was later taken to a Pokémon Center to be healed.
In Zygarde Agitated, Fletchy helped Y as she attempted to take back the Key Stone from Lysandre that was stolen from Korrina. After Solsol managed to take back the Key Stone, Fletchy is taken out by a Hydro Pump from Lysandre's Gyarados.