Silky hair, flawless skin, small farms and exotic body, oriental features up combination that many men find irresistible. Anatomically, the Asian face (particularly women older oriental features) is constructed so that it seems to convey less expression and emotion than the faces of Caucasians. The construction of their faces makes Asian women more "difficult to read" that white women, who tend to express and share their feelings constantly (if we are in the mood to know their feelings, or not !).
This gives Asian women an air of mystery and unpredictability, which is very attractive to men - because we are wired to thrive on challenges and the thrill of the hunt.