Pokabu was owned by an arrogant Trainer initially, but he released it because it lost against a Shikijika during a battle.
When Ash saw Pokabu for the first time, it was trying to eat but couldn't due to a rope tied around its mouth. Ash came forward and helped it but it initially tried to run away from him.
Ash finally cornered Pokabu in an alley and, after removing the rope and feeding it, went back to the Battle Club and told Don George about Pokabu's situation. George explained that Pokabu once belonged to another Trainer but he left it after its defeat by a Shikijika. After that, Mijumaru came to inform Ash that Pikachu had been kidnapped by Team Rocket. Ash tried to get it back with the help of Mijumaru, but it couldn't. Pokabu then forced Ash to let it help him. Ash agreed and commanded it to use Ember in order to get Pikachu out of the black bag Team Rocket captured it in. After that, when Iris had a close look at Pokabu, she found it completely adorable and decided to catch it, but Pokabu decided to go with Ash instead, who proceeded to catch it in a Poké Ball.
In BW005, Ash used Pokabu in his gym battle at the Sanyou Gym, where it battled Pod and his Baoppu. Pokabu's attacks didn't do much damage to Baoppu, but Baoppu managed to hit Pokabu with Fire Punch, Flamethrower and Dig. One of Baoppu's Dig attack sent Pokabu into the air. But Ash commanded it to dive into the hole that Baoppu was in and it managed to bite Baoppu's tail. Although Baoppu threw Pokabu onto the ground, it managed to get up and spun Baoppu around, throwing it to the ground. It used Ember successfully, and then knocked Baoppu out with a powerful Tackle.
