Episode #21 - Bye Bye, Butterfree
It was the season to release all the Butterfree for them to find a mate, and have babies. Ash let his Butterfree out, and Butterfree fell in love with a pink Butterfree. At first, that pink one didn't like Ash's Butterfree. Team Rocket kidnapped (or butternapped) all the Butterfree except for Ash's. Ash and friends and Butterfree went to save all the other Butterfree, and did. Every Butterfree was safe at last, and the pink Butterfree accepted Ash's Butterfree's love. Finally, Butterfree left with the pink Butterfree to cross the ocean and have babies, and will probably never come back.