Hime-chan no Ribbon

The story begins when Erika, from the Magic World, gives Himeko a magical ribbon and pendant that allows her to assume the identity of anyone in the Human World just by looking in the mirror and saying the magic words: parallel, parallel turn me into (name)! The ribbon is a part of Erikas' "Observation of the Human World" training, which lasts for one year. The only drawback is that Hime chan must keep the ribbon and all of its powers a secret from everyone. Hime chan eventually gains other magical items and gets into all kinds of predicaments trying to get herself out of trouble and hide her secret from everyone.