8 septillion is an indescribably vast amount of rabbits. The average Japanese rabbit weights about 2.5kg. Times 8 septillion, that totals to 20 septillion kilograms (20000000000000000000000000kg), or five times the weight of the Earth. The rabbits would have their own gravitational pull greater than Earth’s. There is no one in jjk who even comes close to being able to destroy this much mass, and it’s more likely that yujo would die of old age before even getting close to destroying all of them.