Pain (2011)

Cast
kwon Sang-woo (권상우) as Nam-soon (남순)
Jeong Ryeo-won (정려원) as Dong-hyeon (동현)
Ma Dong-seok (마동석) as Beom-no (범노)
Jang Young-nam (장영남) as Gye-jeong (계정)
Kim Hyeong-jong (김형종) as Redneck (양아치)

Previously known as "Pained"

Trailer

Synopsis
After losing his family when he was young, Nam-soon (Kwon Sang-woo) feels no pain. He cannot feel physical pain and is emotionally barren until he meets Dong-hyun (Jeong Ryeo-won), who calls herself a vampire because she suffers from hemophilia. Unlike Dong-hyun, when Nam-soon is injured, she bleeds from even the smallest wound. As the two grow closer, Dong-hyun suddenly begins to lose his lifelong insensitivity to pain and the hurt of a lifetime washes over him.