K.K. Island

"K.K. Island" is a song by K.K. Slider, introduced as a live-only performance in and given a bootleg recording in. When asked to play this song, K.K. will refer to it as a "secret song." As of this is no longer the case, as it can be obtained readily through Nook Shopping's Special I feel good!s. The song is a rearranged version of the BGM played on Animal Island in the GameCube games.

Blaire (in ), Kevin, Lyman, Medli, O'Hare, Plucky, Tangy and Audie play it in their house if they have a stereo.