You wake up a bit groggy from last night. You wonder if what you felt before was really just a dream. Looking at the city out your window everything looks normal enough. You decide to pull out your phone and look at porn like you do most mornings.
You start looking at porn, but it isn't like it normally is. There's something off. There's a lot more girls with dicks and dudes with vaginas then there should be. There's even a few people with both parts or neither, which shouldn't even be possible in live action porn.
After quickly searching some things on Google, it seems that you've ended up in a reality where genitals and sex aren't the same thing. An equal number of men and women have vaginas and and equal number have penises, and just as many have both or neither.
Oh God, if that's how things are, then what do you have downstairs... you quickly check your body...