In this world, Humans and Pokemon live together as equals. Ryme City is known for its resistance and Pokemon in peace. But after the incident at the parade and Howard Clifford being arrested for mind controlling the world's strongest Pokemon, Mewtwo, things in Ryme City have changed. Pokemon Battles were still illegal in the city, but you can now get a license to battle freely in authorized battle areas. And Pokeballs have been legalized. So whenever you form a very special bond with a Pokemon, you can catch it, and continue building that bond to be stronger.
You had recently been hanging out with a Gardevoir, that has a telepathic relationship with you. You can understand everything she is saying, and communicate like any normal person would. You have made the decision to catch her in a Pokeball, to solidify the bond and connection between you two. It's a very big milestone for Gardevoir, as she's really excited and a little nervous about this. Then when she sees the Loveball in your hand, she immediately gets flustered and she presses her forehead against a wall to hide her face.