“I’ll Show You Mine” is a rather tedious two-hander in which a non-fiction author interviews her once-famous model and ground-breaking “pansexual” nephew for her next book.

As drinks are sipped and awkward truths are brought to light, we’re reminded of what sexuality expert Priya (Poorna Jagannathan) says when Nicky, now a pornographic cartoonist, finally sits down for their weekend-long chat. She is his “aunt” “only by marriage.”

Ahem. As Nicky is a self-confessed ex “slut,” and was once a guy notorious for being uninhibited and not living by “boundaries” society set for him, that should make things interesting. Only it almost never does.

Priya has made a decent career out of exploring her own trauma, the triggers from her abusive dad that remain to this day and how “The Patriarchy” scars women like her. Now, her estranged old man is in a nearby nursing home, his dementia no answer to her need for closure.

And Nicky? He was a model a dozen years ago, famous for coming out and for outrageous acts of public nudity, and infamous for an omnivorous sexual appetite.

To her, he is “the one person I consider to have no hangups.” But she wants to tie that to Nicky’s childhood abuse. And he’s distracted, deflecting, flirting and refusing to talk about his wife and two children or to give too much credence to her “trauma” ideas.

As she’s family (“by marriage”), they have history. She knows a bit and he has some very specific memories, too. Over the course of their long chat, there will be confessions, questions that reveal more about the questioner, constant shifts in the power dynamic and lots of judging.

She is “so tough on yourself,” says boundary-free Nicky.

And you’re “so EASY on yourself,” Priya spits back.

They treat each other with kid gloves, much of the time, because each is desperate for the “comeback” this book could deliver.

Director Megan Griffiths — “Lucky Them” was hers — has animators dress up this bland three-writer screenplay with little samples of Nick’s porno-toons, vulgar depictions of sex acts to enliven that favorite screenwriting crutch “chapter” headings.

Chapters are for novels or mini series. The only reason to include them in a shooting script is that you were too lazy to delete them or so in love with showing your “structure” process that you can’t give them up. They almost never add anything. But here, they’re illustrated/animated with sketched threesomes, sex organs and masturbation, often captioned with a punch line with no punch.

The Duplass Brothers produced this, and they’re fond of talkathons, “mumblecore” their genre used to be called. Adding actual porn (not particularly offensive, just not interesting) must have seemed like a no brainer. To them, at least.

I had hopes, here and there, for a good tantrum from the “expert” over the anything is “acceptable” consequences of a no “boundaries,” shame-free and indecisively “fluid” sexual culture. I mean, how many letters do that figure that acronym can extend to? That “COMMIT” to something tirade doesn’t quite happen.

This “sex, lies and audio recording” has no spark, little chemistry between competent but charisma-starved leads and only one late second act revelation that merits our attention, and a third act surprise that we saw set-up in the first.

Whatever the object, the result is a shrug, a long, often inane conversation about a serious subject that can be dismissed with a single word review.

“Meh.”

Rating: unrated, discussions of sexuality, graphic sexual cartoons, some profanity

Cast: Poorna Jagannathan and Casey Thomas Brown

Credits: Directed by Megan Griffiths, scripted by Tiffany Louquet, Elizabeth Searle and David Shields. A Gravitas Venture release.

Running time: 1:42