Taillow was caught by Goh during his visit to the Hoenn Battle Frontier in Serving Up the Flute Cup!. Afterward, Goh got excited about his new capture, which Hodge mocked him for, saying Goh shouldn't get excited over such a common Pokémon like Taillow. Later, Goh used Taillow to hunt for Wurmple to catch one himself.
In Best Friend... Worst Nightmare!, Taillow noticed Goh's three Wurmple while flying around Cerise Park and started attacking them, which triggered their evolution once they began to fight back against the Tiny Swallow Pokémon.
In A Snow Day for Searching!, Goh used Taillow alongside some of his other Pokémon to find the bone of a wild Cubone, which he later caught.
In Panic in the Park!, Taillow joined Spearow during a food shortage to search for food. When the two found Farfetch'd thinking about eating its leek, Taillow and Spearow were seen drooling over the item. When the commotion led to Goh's Golurk going berserk and flooding the Park, Taillow joined the other small Pokémon and Pinsir to save Goh's three Cascoon.
In This Could be the Start of Something Big!, Taillow attended a surprise party hosted by the Lab members commemorating Goh and Ash's departure.
Taillow is shown to be quite aggressive, attacking Goh's three Wurmple for no apparent reason, even though they belong to the same Trainer. Nevertheless, Taillow is considerate of other Pokémon, as seen in Panic in the Park! where it and Spearow eyed some food but rather than fight over it, Taillow split it in half and shared it with Spearow.
Taillow is often seen in the Cerise Laboratory along with Goh's other bird Pokémon, most notably Spearow.