They're two teenagers, madly in love.

Arin is a rough-and-tumble guy who gets a thrill from dirt bike racing. His girlfriend, Katie, is a striking leggy brunette.

Arin told INSIDE EDITION, “I got a very sweet beautiful drop dead gorgeous girl here.”

Katie said, “I love him so much.”

While they look like a pair of teenage lovebirds straight out of Romeo & Juliet, they are about to reveal an extraordinary secret.

Arin said, “I always considered myself male.”

He used to be a girl and she used to be a boy.

“I’m a girl. I always felt like a girl. I think Arin is the most amazing guy I ever met,” said Katie.

They may be the first boy and girl to go public as a transgender couple.

Arin said, “I really think she's the one for me.”

Katie was born a cute little boy in Tulsa, Oklahoma. His parents named him Lucas.

Katie said, “I grew up as a happy little boy.”

On the outside she was content, but on the inside, there was confusion, struggling with uncontrollable urges to be a female.

Katie said, “I always saw myself walking down the aisle in a white dress. I saw myself as the bride.”

In school Lucas was bullied.

She said, “Bullied and abused. Ridiculed. Ashamed and embarrassed.”

Then he began dressing as a girl, Lucas’ father, Randy Hill, is a retired Marine Colonel, and it goes without saying he took the transformation hard.

Randy said, “I mourned the loss of my son a little bit.”

But, mom Jauzlyn knew she had to say good-bye to her little boy.

Jauzlyn said, “I didn’t care. I wanted to see her happy.”

This year, 18 yr old Lucas underwent a sex change operation and became Katie.

Katie said, “I knew I’d wake up as a full woman.”

Finally, she became the woman she feels she was meant to be. Then love unexpectedly entered her life. It was actually her mom who set her up on a blind date.

Arin Andrews had a story similar to Katie’s -- but in reverse. He was born an adorable little girl who his parents named Emerald. It’s hard to picture him as a sweet little girl in a pageant dress.

“Everyday wore a skirt,” he said.

As a girl, he found it impossible to control powerful male urgings.

Arin said, “It was torture every day. You don't recognize yourself in the mirror.”

When he broke the news to his mom, it didn't come as a total shock, but it was a blow. Arin’s mother, Denise, said, “I’m losing my little girl. I was pretty much numb.”

His mom still has a closet full of old dresses.

Six months ago, Emerald changed her name to Arin and started taking male testosterone shots. He began shaving and then he went out on that blind date. Magic struck.

Arin said, “I was like, ‘Oh my God. Too pretty to be transgender.’ I was shocked at her beauty.”

Katie thinks he's sexy.

A little girl's once butter-soft skin is no more. The hair on Arin's legs is, well, all-guy, even under his arms. His dad, Mitch showed in him the ropes about how to tie a knot.

Mitch said, “She doesn't like my little girl anymore. She's happy and healthy. He is. I have a hard time referring to him as a he.”

The 16-year-old is also lifting weights to build muscle mass and working toward building a six pack.

Arin said, “I want be pretty ripped.”

Both dad's have now come around and embraced their transgender children.

Since the two teens are about the same size, they wear each other's clothes. Katie even slips into her boyfriend's old bikini's.

The two teens says they couldn't be happier together. Clowning around the pool, enjoying each other's company as boyfriend-girlfriend. Looking at them now, you would never know that she was once a boy and he was once a girl.

Arin said, "She is the one for me."