Growlithe was Koya's first Pokémon when he was still young. They were a good team before Growlithe was defeated by a water-type Pokémon and badly injured. It became later scared of Koya after the battle and Koya then decided to become stronger.
Growlithe was later used by Charon. Koya was shocked by Growlithe's appearance and tried to get through to it but it failed. Growlithe used Flamethrower on Hareta and Koya, who both dodged the attack. It then used Flame Wheel on Hareta but Koya blocked the attack himself. In order to free Growlithe, Hareta called his Empoleon and used Surf on Growlithe. Koya tried to stop Hareta from ordering the attavk because he was scared that Growlithe would fall back to the experience it had in the past. Surf knocked out Growlithe and it destroyed the mechanism that was attached to Growlithe in order for Charon to control it. Koya ran to Growlithe and they were reunited by hugging each other.