Hello Kitty with claws: Gloomy Bear
Mori Chack's Gloomy Bear and his other characters are a hyperviolent answer to Hello Kitty and the rest of the Sanrio gang. Be aware that most of them are bloodier than this tame sample.
As intriguing as Gloomy Bear is (another example of Gary Snyder's circumpolar bear cult?), I like the bloodless but dark humor of some of his other work better, which reminds me a bit of Edward Gorey or Gahan Wilson cast into Sanrio-style graphics.
Of course, for other answers to Sanrio there are the classics Hello, Kali and Hello, Cthulhu. (Via I Love Everything, who got it from GMTplus9.)