Well first of all i have no idea about ayu's song's being written in different cases.
secondly, her name. The name "Ayu" is used by her fans. it's what her fans call. like a nicname basically. Ayumi Hamasaki is her actual name of course. This is all the basic stuff but the way u write about it, it sounds more than that. like there's another side of ayu no one has ever heard of, or something like that. But that's a very interesting theory, gohan
