Noting Japan's latest social trend, two paperback photo books — both with portraits of hamsters' rear ends — have experienced surprising and still-growing printing runs. Japanese society has long seemed easily captured by anything kawaii (or "cute"), according to a May Wall Street Journal item, and a rep of one book's publisher called his volume "delightfully cute." "I can't stop smiling," he said, "when I see these butts." The books are Hamuketsu (hamster buttocks) and Hamuketsu – So Cute You Could Faint. The Original Hamuketsu debuts this month.