dream didn't copy anything. dream made a tribute album for avex artists and covered several of them, including globe and ayu for example. To cover doesn't equal to copy.
And as far as I know both fairyland and Depend on you are ayu's originals.
also if Pride and rainy day are technically not a cover, youy should also add B&D, Ladies Night and Beautiful day.
There's also songs that ayu sings that have sampled compositions:
i.e:
-"walking proud" from some Kinki Kids songs called "Angel" if I'm not mistaken
-"Free & Easy" sampled from "No Amen" a movie soundtrack for that insane Joan of Arc movie.
-"Pride" sampled from the obnoxious "crucified" song.
-"SEASONS" sampled from Roxette's "Listen To Your Heart" (nah, this is just a joke of mine
...still it does sound oh so inspired LOL)
http://www.youtube.com/watch?v=3sJPUTTfNbg
-"GAME" sampled the SE from Space Invaders (???) j/k again