'Kawaii' is Japanese for cute. Well, more accurately it's a cry uttered by teenage (and wannabe-teenage) girls in a squeal, so it translates usually to "aw, so cute!". Those guys down there induce this cry. Kawaii culture is omnipresent in Japan, and it's slowly leaking its way into the rest of the world.
This site will offer everything you will ever need to know, from why cute is appealing to what this means for our culture, but for what it's worth I'm backing this guy to be the Next Big Thing® - Hamtaro.
4:54 pm
Simon
