S1 E6: Ash and Riolu are training hard for the World Coronation Series…perhaps a bit too hard, as Pikachu ends up feeling lonely and jealous. When Delia comes for a visit, her love for Pikachu is abundantly clear, and Pikachu cheers up a bit. After she leaves, Pikachu decides to follow her to Pallet Town. Mimey tries to get Pikachu to return to Ash, but Pikachu refuses, so the two Pokémon begin their journey. Although it’s perilous at times, they finally arrive—and who should suddenly appear but Ash and Goh! Ash apologizes to Pikachu for making it feel lonely, and all returns to normal as Delia welcomes everyone with a meal.