Remember SeoHyun thanking Ock Joohyun? That was after SeoHyun's special appearance at her concert last January 22.
There was no video at that time, but not anymore. You can now enjoy SeoHyun's wonderful stage with Ock Joohyun. Here's their clip performing the song titled 'For Good'~
SeoHyun and Ock Joohyun are close friends, and prior to this, SeoHyun has said many times that her rolemodel is Ock Joohyun.