But, the interresting thing is ayu seemed to have a part in the real game.
Have a look down there at the bottom of the page - ayu is credited there as "Other Crew" Singer: Love Destiny. And IMDB isnt wrong in most cases.
http://www.imdb.com/title/tt0234713/fullcredits
But i wonder if this is only in the japanese version of the game couse i have the european one (unfortunetly never played it through). Maybe i should do that to assure that she really has Love Destiny in there...
Oh and that songe from Kazaa isnt her for sure, i had that one too.