More info on the drama CD, mostly casting. From what I see is that the original names were changed into the Japanese version. If someone could translate the Korean, if it is important, that would be great.
http://kanamaria.egloos.com/1511004
Name Change:
Nae Hye-Young=Takanashi Erina
Caroline=Takanashi Caroline
Myung Jin-Ho=Mikado Kenichi
Ha Ji-Soo=Sugahara Mai
Park Jae-Kyung=Honda Akane
Eun Ami=Nagumo Ami
Cha Young-Ki=Hanai Hiro
Voice Actor Casting:
Nae Hae-Young=Inoue Kikuko
Caroline=Kawasumi Ayako
Myung Jin-Ho=Sugita Tomokazu
Ha Ji-Soo=Nakahara Mai
Park Jae-Kyung=Minami Omi
Eun Ami=Goto Mai
Cha Young-Ki=Miura Hiroaki