Dexio, along with Sina, are first met by the player in Route 4 where they discuss about Flabébé and the Fairy type. Dexio then introduces himself as a Pokémon-voyage veteran who received his Pokédex from Professor Sycamore two years beforehand. In the gate to Lumiose City, Dexio tells the player about friendship and gives the player TM27 (Return). After arriving at Lumiose City, Dexio tells the player to follow Sina to Professor Sycamore's lab.