If you want a serious answer, read: Race Evolution and Behavior - A Life History Perspective 3rd Unabridged Edition 2000 by John Philippe Rushton. The answer is on page 162. >There are racial differences in the production of odor produced by the apo­crine glands (J. R. Baker, 1974). These glands are associated with underarm and genital hair and become active when people are frightened or aroused. Blacks have more and larger apocrine glands than Caucasians and Caucasians more than Orientals. The Sino-Japanese are very sensitive to smell and doc­tors specialize in treatment for body odors. In Japan, a strong odor used to be sufficient in the early part of this century to warrant the sufferer being exempt from military service (J. R. Baker, 1974: 173). In addition to having larger and more body odor glands, they generally lack personal hygiene vs. other races and are less likely to keep a tidy house. You are probably getting decaying KFC and nasty dirty laundry smell mixed in with the fermenting apocrine gland stench.