Japanese girls are so kawaii, oni-chan! Just kidding. Honestly, it depends on the actress. I think the cutest actresses (collectively) I have seen are Taiwanese. My personal favorites are Korean (Yoon Jin Yi, Han Ji Min, Wang Ji Hye, Kim Yoo Ri) but so much of it has to do with the character they are portraying. I am attracted to the emotion and the characters as much as the appearance, so if you're lacking that, you're lacking attraction..