Ah, it's Totoro-pan. I love that stuff.
It's been around roughly 20 years or so... pretty much a staple of Japanese bakeries. I'd forgotten that Totoro-pan wasn't common knowledge in the West.
Still, it's not only cute - it's quite tasty. Think 'Eclair with cream frosting topping and a slightly thicker, flakier crust'. Of course, the whipped cream filling is the best part.
Or the best part could be the fact that it's like drinking the sucrose-laden blood of Taitoro... your choice.
-Djinn