Smoochum belongs to the Pichu Brothers' friend group in this animated special. It engages in events tied to Meowth's party invitation, initially seeming undelivered to the group. Smoochum accompanies the Pichu Brothers and fellow Pokémon friends on the adventure arising from this confusion. The story resolves as the group finds their delayed invitations, leading them to attend Meowth's party collectively. Smoochum functions as part of the unified friend characters advancing the main plotline of invitation misunderstanding and resolution.