Lea Michele revealed that she gave her co-star and close friend Jonathan Groff a surprisingly intimate anatomy lesson while they were working together on Spring Awakening.

The actors reflected on their experiences in a documentary that celebrates the musical's 15th anniversary. The project, Spring Awakening: Those You've Known, premieres on HBO May 3.

One noteworthy and eyebrow-raising revelation came before the official release date. According to People, Michele opened up about the time she gave Groff, who is gay, an up-close look at her vagina.

"At one point, I literally showed him my whole vagina," she says in the documentary.

You might be wondering why she did that; according to Michele, there was indeed a reason.

"He was like, 'I've never seen a woman's vagina before. Would you show me?' And I was like, 'Sure.' And I took a desk lamp … and showed him. That's how close we are… But I've never seen Jonathan naked. I've never seen his penis."

In the doc, Groff also opens up about how the musical, which featured an intimate sex scene between his character and Michele's, made him nervous about outing himself.

"I wanted the choreography to tell me what to do and give me the moves and allow me to express myself," he says.

Clearly, Michele and Groff were very comfortable with one another. After Spring Awakening the duo worked with together again on Glee.

In another interview with People, Michele made an offer to her former co-star that draws a parallel to her character from the popular TV show. How so? She offered to become Groff's surrogate if he ever wanted to have a child.

"I'll carry your baby," she told him.

"I love being pregnant," Michele added. "It's so much fun."

Glee fans will likely recall that Michele's offer to carry Groff's baby closely mirrors a plot point from the show. In the final episode, it was revealed that Michele's character Rachel Berry agreed to carry a child for her friends Kurt Hummel (Chris Colfer) and Blaine Anderson (Darren Criss).

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