Lucky K.K.
From Nookipedia, the Animal Crossing wiki
"Lucky K.K." (アイリッシュそんぐ, Irish Song) is a song that K.K. Slider plays. It is fairly fast-paced and has an old Irish theme to it. Whitney, Hopper, Aziz, Sterling (in Animal Crossing: New Leaf), Vic and Rocco play it in their homes. Lobo and Lolly appear on the cover.