name of actress

If you are referring to the near beginning of the movie, I believe it is Ji-won Ha.

its ha ji won. a very famouse actress in korea. such a shocker to see her in this film though. especially in that sex sequence when all her friends were having sex and they all took their clothes off and you could see their upper body parts and then it was her turn and its the usual bare shoulder.

don't know how many people were left feeling dupped but i thought she would go all out too.