殺人ウサギ
A small white [[rabbit]] from [[Monty Python and the Holy Grail]] that guards the Cave of Caerbannog. It appears innocuous, but proves deadly enough to kill some of Arthur's knights. Only the [[Holy Hand Grenade]] is capable of defeating the beast.

The Killer Rabbit has become a popular metaphor for something that looks cute but is extremely dangerous.
killer rabbit of caerbannog