For this song, Pikachu is wearing sunglasses, so I think we can call him Pikataro.
Pikotaro and Pikachu will be combining their talents/powers to create a new song, titled “PIKA to PIKO” (with “to” being read like to, the Japanese word for “and”).
Pikachu is one of those rare cases where an anime/video game character becomes a full-on celebrity.
Pikotaro and Pikachu want to give the world something to smile about.