4. Candiru - This is a fish/parasite local to the Amazon that crawls up your urethra (that’s your pee hole) or vagina then drives hooks in so you can’t pull it out. It has been said to cause so much pain that men would rather cut their penises off than stand the pain long enough for an alternate treatment. Candiru are very rarely documented and they’re only in the Amazon, so you probably don’t have to worry. But you should still worry. There’s a creature that has evolved to drive hooks into your penis. You should constantly be worried.
(Source: College Humor)