The Naughty Notes are a bunch of annoying notes who first appeared in Into the Fourth Dimension. They took over the music at Meloetta's Musical Mess in the Fourth Dimension. They also work for Dimentio, as revealed when one of the notes said that the instruments will belong to Dimentio. The personalities for the Naughty Notes represent street talk. The purple colored note (middle) is the leader of the Naughty Notes, the green note (right) is second in command, and has a very street-like vocabulary, which is hardly not easy to understand, and the yellow note (left) grunts instead of talking. After the Naughty Notes took over the music, they played an 8-bit version of the song What Is Love, which annoyed everyone else. After everyone got enough D-Stars, the Naughty Notes disappeared.
They later reappeared after Dimentio lost his sanctity and called everyone worthless fools. The Naughty Notes were offended by this, and decided that Dimentio betrayed them, and so they moved over to the good side and renamed themselves to the Nice Notes.
- The Naughty Notes look exactly like the evil note enemies from Band Land, a world from Rayman.
- The Naughty Notes are one of the few characters in Into the Fourth Dimension who do not have any other dimensional counterparts, but it can be intended that the evil note enemies from Band Land in Rayman are the normal dimension counterparts of the Naughty Notes.