As someone mentioned before, this is Kirarin, not Koharu. Let me explain: the mini album is called "Kirarin Revolution Song Selection", and as far as I know, Koharu only plays the Opening song, and only for the first 17 episodes. She plays the voice of the main character, but she does not sing all the songs this character plays in the series. From episode 18 and on, the opening song will be a C-ute song. So this mini-album will have only 1 or maybe 2 songs (someone said she does the Ending song too) by Koharu. The second single is the real news here, but still it's Kirarin.... Koi Kana has sold very well because it's aimed at the kids that watch the anime, and it's those kids that want to have Kirarin's song (as a friend living in Tokyo wrote a few days ago, most kids don't even know the singer's name is not Kirarin). So I would not say she's living to her "Miracle Girl" title.