Being a secret military facility (and probably also because "Top Secret Skin-Eating-Gas Cannery" is hard to fit onto a tiny dot on a map), Okunoshima was erased from official maps when the factories were cranking out poison during the war. Even after the facilities were shut down and abandoned, Japan decided to leave it out of the maps due to their shameful past. Can you blame them? Over the decades, however, people started visiting the island again, because the thrill of creepy abandoned places always overrules survival instinct sooner or later. What these visitors found was scores of cute, fluffy bunnies, skippity-hopping all over the island.
And, just like that, the most brutal war in human history was totally worth it.
Hundreds upon hundreds of bunnies. Just bouncing around the abandoned facilities, cavorting amongst themselves without a worry in the world. They aren't the usual shy variety, either -- the instant people set foot on the island, bunnies gather at their feet and start begging for treats.
But how does an island best known for its role in wartime atrocities evolve into a haven for free-range bunnies? The most logical explanation would be that the rabbits are descendants of test animals that were released when the facilities were shut down. The truth, however, just adds to the fairy tale vibe of the island: In 1971, a nearby elementary school was having difficulty caring for their class pets. They had to get rid of their eight rabbits. Somehow, they ended up choosing the creepy abandoned chemical weapons island as the perfect place to dump said rabbits, because apparently the whole "teaching students responsibility" thing wasn't really in vogue back then.
Sadly, this woman lasted another seven seconds before the horde consumed her.