The Clefairy's social interactions are heavily based around music and dance, and indeed their very names are rooted in music ("clef" being the French word for musical key), as are several of their powers (such as Metronome and Disarming Voice). Rhythms and singing are instinctive and seemingly vital to each Clefairy and to the species itself--another point of similarity between Clefairy and mythological fairies. The moon-music connection briefly mentioned on the Mythology page also comes into play here, as many musicians (including myself) find inspiration more at night than during the day.
As a singer, pianist, and composer since the age of twelve, I find myself identifying with the musicality of the Clefairy, since so much of my life is based in music. Melodies and chords for me became a refuge and a source of enjoyment, a way I could conquer my learned shyness, and I believe it's the same for the Clefairy, whose highest musical and social expressions come into play when they sing and dance together. There's a sense of community between performers that is not often found offstage or outside the auditorium, and the Clefairy seem to enjoy it as much as I do!
Thus, I thought it only appropriate on this dedication to Clefairy that I include a selection of music suited to describe this sweet yet mysterious Pokémon. Browse through, and you'll get a little window into how I perceive Clefairy musically. ♥