[Ghoulish Delight]

I wouldn't be so quick to pass it off as psychological. There have been some surprising studies involving human smell, pheremones, and genetics. For example, I read a study where women smelled shirts that men had worn for a couple days. The results showed that the women preferred the scent of men with complimentary immune systems (i.e., if the woman had high counts of antibodies against diseases a, b, f, h, and i, she'd most prefer a man with high antibodies counts against diseases c, d, e, and g). Seems to suggest a genetic advantage, giving offspring the highest chance at a robust immune system.