If you can believe it, Lena Dunham exposing her vagina on an episode of Girls is not the most naked she's felt on set.

On last night's (April 10) episode, Dunham's character, Hannah, spontaneously broke up with her boyfriend, Fran, during a road trip and insisted he leave her behind at a rest stop. Luckily, Hannah's pal Ray was around to pick her up (in his new traveling coffee truck, no less), and to thank him for his generosity, Hannah leaned over for a mouthful of something other than the day's preferred roast.

Perhaps a little unexpectedly, Dunham says in the "Inside the Episode" clip above that filming the moment is the most exposed she's felt on set, but explained that she nailed down a winning strategy to cope with awkwardness.

"I learned a trick which is to go like that with your thumbs, so that you actually have something in her mouth," she says, thumbs outstretched toward her face, in the segment. "I've done a lot of on-screen nudity, and somehow I felt the most vulnerable giving a fake-blowjob to my two thumbs."

And while the moment may have been jarring — even to longtime fans of the show — Dunham argues that it fits in with the context of the story.

"It seemed inevitable that at some point Hannah and Ray would have some kind of sexual interaction," she insists. "What I'm happy about is that it was something as grotesque as a thank-you blowjob in a coffee truck."

Check out the clip above for more behind-the-scenes scoop from Season 5, Episode 8.

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