Seo In Young and 2NE1 wears Mark Fast and Faster by Mark Fast

Seems like Seo In Young and 2NE1 both share the same taste in clothes. Here is one designer which they have been seen wearing recently :

Mark Fast (Spring/Summer 2010)
Seo In Young (서인영) first wore the dress to Hite/Dry Finish launching event on August 5, 2010. Styling the outfit with Camilla Skovgaard Wedge Ankle Boots (see post here).

Subsequently, 2 members of 2NE1 were seen sharing the dress.
Minzy wore it in 2NE1's 'It Hurts' music video. Completing the outfit with Chanel accessories and Azzedine Alaïa Pony Hair Boots.

Sandara Park (박산다라) then wore the dress to SBS Gayo Daejun on December 29, 2010. Instead of the Chanel accessories, she opted for a fur shrug around her neck and Rick Owens boots.

Mark Fast's diffusion line, Faster by Mark Fast
Seo In Young (서인영) presented her new music video with a bang!, revealing her futuristic new hairstyle and Faster by Mark Fast dress. Her outfit was completed with dangerous spiked high heels.

Park Bom (박봄) performed to 'High High' on SBS Inkigayo on December 19, 2010. Her outfit is styled with a pink fur shrug around her neck and Christian Louboutin Bikiki 140 Pony Pumps.