As you might recall from the instruction manual of Super Mario Bros. 2, the mini-boss character Birdo is, in certain versions of the Marioverse, a transvestite: He's a pink boy dinosaur who wears a pretty ribbon because he thinks he's a girl, and spits eggs from his mouth because....
Because....
He doesn't have a vagina?
At any rate, one of two things has happened since the 1988 release of Mario 2. Either Nintendo retconned Birdo's gender crisis out of existence by turning him into a her, or, if you're following Reitz's interpretation, Birdo had a sex change operation. Either way, Birdo's referred to as a "her" in modern games like Mario Tennis.
Oh, but not anymore. Not in Captain Rainbow.
Shortly after the prologue of Nintendo's latest Japanese Wii game, one of the first characters that you, as a superhero stranded on a mysterious island filled with past-their-prime Nintendo misfit characters, have to help is Birdo, who's been jailed.
Birdo is seen by the island's robot police officer as he/she comes out of a public toilet. (The line he delivers as he comes out: "Wow, that was huge. That was like giving birth.")
The officer throws him in jail for using the ladies' room when he's clearly a man. Birdo asks you to go to his/her house and find "evidence that I'm a woman." So you do. This is how it happens. As you walk into Birdo's bedroom, you hear ... a buzzing. The pillow on her bed is vibrating and buzzing. You walk up to it, and Captain Rainbow looks under the pillow to find ... an item that's censored out on the screen. It's covered up with a question mark. "Proof that the owner is a woman," it says, leaving it at that.
So you bring what is in all likelihood Birdo's vibrator back to the police robot, who accepts it, whatever it may be, as prima facie evidence that Birdo is a chick.
Yeah, I have absolutely no idea how this would fly outside Japan, either."