Reddit sensation "Diphallic Dude" pens a memoir detailing what it's like to have a lefty and a righty in his pants.

A year ago, a man with two functioning penises did a hugely popular Reddit AMA about his unique condition, technically known as "diphallia." He answered seemingly every question the collective internet could throw at him, from biological functions (yes, he pees from both of them) to psychological fallout to porn aspirations.

But that only stoked more interest in his situation, so he started a (very NSFW) Twitter and Tumblr, which have now led to a memoir, titled "Double Header: My Life With Two Penises," available on Amazon.com as an e-book.

"When I 'came out' to the world on Reddit, I had no idea anyone would really care that much about me," Diphallic Dude -- born in 1989 -- writes in the intro. But fortunately, he didn't feel judged from revealing himself to the world: "Fascination about my double d--ks is one thing. However, it's the wave of acceptance for being myself that inspired me to write this book."

It wasn't always that way. DD's parents warned him not to reveal his condition to others, he writes, and once he did, he experienced all kinds of negativity and prejudice, both because of his penises (the first girl he had sex with told the entire school about him) and because of his bisexuality. That's why he now wants to spread acceptance of everyone's differences.

"I've gotten so many messages from people who need encouragement for one thing or another," DD told Rolling Stone in a recent interview about the book. "With so much negativity in the world, the ability to bring something positive to the table is a great feeling."

Just don't expect to find out his real name any time soon. This author is keeping his pseudonym.