K.K. Ragtime
From Nookipedia, the Animal Crossing wiki
"K.K. Ragtime" (ラグタイム, Ragtime) is an 1890s-styled song by K.K. Slider. It has a ragtime piano syncopated in a melodic line and regularly accented. It sounds like a song played in a western saloon or a line/square dancing song. This song can also can be heard on the TV at a certain hour of the day on a comedy show where there is a young man and woman doing comedy for the audience on stage. Bob, Moe, Bones (in every game up to City Folk), Broccolo, Melba, Anchovy and Mathilda (starting as of Animal Crossing), and Candi (in Animal Crossing: New Leaf - Welcome amiibo) have it in their houses.