TMI! Lea Michele Gave Jonathan Groff a Very Explicit Female Anatomy Lesson

Nothing stands between them — not even underwear. Best friends Lea Michele and Jonathan Groff met while playing lovers on Broadway in Spring Awakening, and the new HBO documentary Spring Awakening: Those You’ve Known reveals that they didn’t just expose themselves on stage.

Michele, 35, and Groff, 37, played Melchior and Wendla, who have a sex scene on stage during the rock musical, but the Glee alums got up close and personal backstage.

“At one point, I literally showed him my whole vagina,” Michele recalled in the documentary. “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.”

Groff is openly gay, so he had no experience with the female anatomy until Michele gave him a lesson. The doc detailed this story as they reunited along with the rest of the Tony Award-winning musical’s original cast for a 15th anniversary concert.

Michele said she opened up about the bizarre backstage moment because she felt so comfortable with the producers. “Honestly, the great thing about this documentary is it’s a wonderful microscope into who we are as individuals, and not just who people think we might be,” she told Entertainment Weekly in an interview published on Monday, April 25. “Radical Media and the incredible production team behind this documentary, we felt so safe and comfortable with them.”

The “Christmas in the City” singer added: “It was so wonderful to talk about this material as an adult and get asked real serious questions. Not like, ‘What’s it like to have sex with Jonathan Groff every night?’ So I just felt really comfortable with them. With that level of comfortability came a story of just what goes on behind closed doors between me and Jonathan Groff. That’s only one of them. There’s a lot of other things.”

Groff giggled as he added, “There’s a lot more than that story, for sure.”

Michele laughed, concluding, “That was like a Thursday.”

The Mindhunter alum controlled his laughter enough to tell Vulture‘s “Stage Whisperer” newsletter on Monday that Michele’s private parts are “beautiful.” She quipped, “Thank you so much for saying that, because you didn’t say it in the documentary!”

The comedy was necessary backstage, according to the BFFs. Spring Awakening deals with dark subject matter, including rape, abortion and suicide. Addressing the difficult topics during eight shows a week took a toll on the cast.

“Playing these characters was really weighing on us emotionally, and for myself my well-being a bit. I was really ready to step out of that world,” Michele explained in an interview with Billboard on Monday. “I remember walking off stage, literally covered in blood, sweat and tears, and I looked at Jonathan and said, ‘I want to be in a show that’s the happiest show in the world. I want to do musical numbers with fireworks and tap-dancing with Kristin Chenoweth.’”

Sound familiar? She added, “I guess put it out there and it’ll come to fruition – because three years later I ended up on a show called Glee – but I truly knew I needed to do something a little lighter.”

Michele played Rachel Berry for six seasons on Glee, often opposite Groff, who popped up intermittently as Jesse St. James.

Spring Awakening: Those You’ve Known premieres on HBO Tuesday, May 3, at 9 p.m. ET.

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