I tought it was Haruka at first too... at least it looks like her in the thumbnail. But the hair style is totally different and she's using twintails... I doubt it's her.
You're probably right, since it was in an H-mag (COMIC Kairakuten 05/2008), it's not likely to be a copyright character.
Still, rather heavily "inspired" by her, if not outright "as close to Haruka as I can get without risking a lawsuit". I'll just keep pretending it's Haruka...