This is the PV of the song AH by After School featuring Marco.
This is the link to the song: http://www.imeem.com/groups/2tF-jia9/music/Y8LvXIUu/after_school_ah/
The group are composed of:
Park Ga Hee (박가희)
Lee Joo Yeon (이주연)
Yoo So Young (유소영)
Kim Jung Ah (김정아)
After School First Single - New School Girl
Release date is January 23, 2009.