Thirst stars Song Kang-ho (The Host - watch it now, J.S.A. - watch it now) and is directed by the amazing Park Chan-wook (Oldboy, Sympathy For Mr. Vengeance). The poster is a photoshop by _dementia inspired by the NeoGAF thread about the movie. Turns out this imagery has been slightly modified after the original was banned in Korea.
Here's the trailer.