this is my interpretation of the song:
wonderland cos it is about ayu's childhood
this is cos of the music box sounds (orgel), it is a little girl's dream to have a music box
the orgel sound makes the song sound innocent, and we regress into our childhood.
but then there are a lot of nasty laughs from an adult male, this may represent her father.
innocent childhood shaken and pierced by nasty and cold laughters. this is a sharp contrast.
so in short, this track is about her unhappy childhood.
what do you think? (helo masa, do you wanna do a psychoanalysis on this song?)