Meet the identical twin sisters who share everything — including a fiancé

• Anna and Lucy are identical twin sisters featured on the TLC show "Extreme Sisters."
• They do everything identically, including speaking, eating, and dating the same man.

Anna and Lucy DeCinque call themselves the "most identical twins in the world," and work to live up to their self-proclaimed title.

They're engaged to the same man, have the same bathroom schedule, and work the same job (one for a salary the other as a volunteer, for legal reasons, they told me). They also complete each other's sentences, or speak in unison.

The twins are one sister duo featured on TLC's show "Extreme Sisters," which debuted its second season on January 23. On it, the DeCinque sisters show their shared life, which includes being engaged to their fiancé Ben, who proposed at the end of season 1 after 11 years of dating the twins. During season 2, the twins also discuss their dream of being pregnant at the same time, then give motherhood a test run with life-like baby dolls.

Viewers often critique the sisters for their close bond, the DeCinques said. But they don't regret their lifestyle and said it's the great joy of their lives.

When I asked them how they felt after filming season 2, they responded in perfect sync. "The show's made us more extreme," they pause, then one starts speaking slowly as the other catches pace. I picture them through the phone, locking eyes and reading lips.

"It made us realize how much we love each other and really can't live without each other. And we work as one person," they finished.

Their fiancé Ben is the first partner they've ever shared

The DeCinque twins have been dating Ben Byrne for more than a decade and he proposed to them with identical rings that had three bands each at the end of season 1 of "Extreme Sisters."

The twins told Insider he's the first man they've dated together because he wasn't "sleazy," when they presented the idea to him. They said they fell in love with his personality, sense of humor, and ability to treat them how they want to be treated.

"He always treated us equally. He never separates us, and he doesn't want to take us out separately," the twins told Insider, adding that if he kisses one sister, he always kisses the other right after.

They said that Instagram users often leave judgmental comments about their lifestyle, which they delete from posts, but they also get supportive comments from fans of the show.

"People need to accept it. Maybe people don't agree with it, but we're not hurting anyone. Love is love. That's what we've always said," they said.

For now, the trio remains engaged, but can't get married because it's illegal to be married to more than one person in Australia where they live.

Anna and Lucy want to be mothers, but only if they can do it together

This season, Anna and Lucy revisited a season 1 conversation about pregnancy and motherhood, saying they want to have babies at the same time.

But during a heartfelt conversation, one of the sisters, Lucy, reveals she's had trouble getting pregnant.

They told Insider that the conversation brought them closer together and made them realize they'll be happy whether or not they become mothers, as long as they can do the same thing.

"We feel like we're one person. We can never, ever be apart and we would never choose to be," they said.

"This is how we want live our life. We want to grow old together, die together."

The finale of "Extreme Sisters" airs March 20 at 9 p.m. EST on TLC.