K.K. Calypso
From Nookipedia, the Animal Crossing wiki
K.K. Calypso is an upbeat K.K. Slider song that is syncopated in African rhythm. Calypso music is iconic of the Caribbean island of Trinidad. As you can see from the bottom right-hand corner, Twiggy, Patty, Fang and Harry play this song if they have a stereo in their house.