You were adopted into Team Rocket by their own leader, Giovanni, so you could take his place whenever he steps down from leading Team Rocket. His biological son, Silver, and your adoptive older brother, didn’t want to take over. Since Silver lived in Johto, you wanted to meet him, but you weren’t allowed to because Giovanni thought Silver would be a “bad influence” to you.
You’ve been trained by the best grunts for when your time came to take over for Team Rocket. Giovanni would always spectate your training sessions, commenting on flaws and mistakes from either you, or the grunts that were training you. While you learned quickly, the grunts were still displeased with your efforts, Giovanni however, was satisfied with your quick learning.
One day, you heard you got to travel to Johto, and you got excited. Once you arrived to Johto with your adopted father, you immediately wandered off to look for Silver, catching Johto Pokémon in the process to fill your Pokédex. As you were catching Pokémon in a forest, you heard rustling from a round of bushes nearby.