Ash first received his Pikachu from Professor Oak in I Choose You, but at first Pikachu refused to trust him and didn't listen to his trainer. But after Ash saved his life, Pikachu trusted Ash. Pikachu became a target to Team Rocket who are determined to capture him for their boss, Pikachu has a fear of Team Rocket because they are trying to get him. In one episode, he clung to Dawn's leg scared because Team Rocket was going after him. He also doesn't like Team Rocket and wants to stay with his trainer who protects him from them.
Ash's Pikachu is loyal, friendly, fun-loving, kind, and caring to his trainer. He loves his trainer very much. He also has a fascination for ketchup and cries when his ketchup is gone. He also loves his friends and adores Misty, one of Ash's former traveling companions. He loves to play with other Pokemon and also loves helping his trainer win gym battles.