Is that Kotori? No, she’s a new girl called Alyn from an upcoming game Fairy Fencer F by Compile Hearts XD, voiced by Ookuba Rumi (Chinatsu from Yuru Yuri, Yuzuko Nonohara from Yuyushiki). [see Official Site]
There is a promo vid here. Scheduled for release 19th September for the Playstation 3. No it won’t get translated, don’t even dream.