In college, I had a male friend who once asked me if menstrual cycles had anything to do with the moon.

He asked it half-seriously, with a sheepish tone that implied he didn’t really believe that the moon’s gravitational pull caused blood to ebb and flow like the tides, but, well, just making sure, there was definitely no connection there, right?

A lot of my female friends have stories like these. One of them knows a guy who thought women could choose to begin bleeding the way people choose when to go to the bathroom. One time, when she mentioned something about needing to find a tampon, he asked her why she couldn’t just hold it in.

Another friend met a man at a bar who, after spotting a pad in her open purse, asked her if it was hard for women to poop during their periods. Not a great opening line for multiple reasons, but one of them is: Over the course of their very brief conversation, it became apparent that he believed women menstruated out of their butts.

Harry Finley believes none of these things.

Finley, 73, is the founder of the now-defunct Museum of Menstruation, or MUM. For nearly 20 years, he’s operated the museum’s website, a collection of thousands of pages of menstrual memorabilia from reusable pads to old magazine advertisements. Before that, he was the proprietor of the brick-and-mortar MUM, which he ran out of his basement in New Carrollton, Maryland, from 1994 until 1998. Through it all, he believes, he’s also been a beleaguered soldier, a one-man war against the taboos surrounding menstruation.

In recent years, this war has become easier to fight. Lammily, the doll nicknamed “normal Barbie,” now comes with period accessories. This summer, a woman ran the London Marathon without a tampon, bleeding onto her running pants. HelloFlo ads are adorned with hashtags like #MakeItVagical. In 2011, a British artist created the “Menstruation Machine,” a sort of high-tech chastity belt for men who wanted to experience the feeling of having a period.

Here’s the thing, though: Most of this taboo-busting is being driven by women, who are making peace with their bodies and dragging something considered shameful into the open. Men are welcome to belong to this movement, and to contribute to it. But for Finley, that’s not enough.

* * *

If the woman proudly embracing her period is slowly emerging as a cultural trope, it’s long predated by the trope of the man who’s laughably clueless about the whole thing.

In defense of the moon guy and the butt guy and the hold-it-in guy, a lot of men learn about periods by piecing things together on their own. In one 2011 study, researchers asked a group of college-aged men to describe how they had learned about menstruation. The responses had a few common themes, the authors observed: The men had largely picked up snippets of knowledge from female family members and, later on, girlfriends, but by and large were still fuzzy on the basic mechanics of the female reproductive system. “Boys’ early learning about menstruation is haphazard,” the researchers wrote. “The mysterious nature of what happens to girls contributes to a gap in boys’ knowledge about female bodies and to some negative views about girls.”

At any rate, it makes for okay comedy. See here, here, and here for riffs on the same idea: LOL, guys don’t get periods. It’s one model of a limited number of models for the ways men can talk about menstruation: ignorance, or an academic interest, or even a fetishistic one.

Finley’s doesn’t fit into any of the models. A man who lived and breathed period kitsch for so many years is not ignorant, but neither is he a scholar. His curiosity doesn’t stem from anything sexual, either: “With girlfriends, the subject never came up. And if it did come up, I think I would have run,” he told me. “I just wasn’t interested.”

Finley traces his interest back to the identity it created, the chance it afforded him to be a little subversive. “The museum was kind of an act of freedom for me,” he said. “I grew up in a military family doing everything right, the straight and narrow. When other kids were swearing and stuff, I never did.”

His attraction to all things menstruation began when he was living in Germany as a graphic designer for the U.S. military in the 1980s. He started collecting old menstrual-product advertisements, he said, because the artist in him liked looking at renderings of women’s faces.  But as his collection grew, that appeal was supplanted by what he called “the buzz of the forbidden”—the more ads he amassed, the more he felt like he had finally discovered the rebellion that eluded him in his early life. Here, finally, was a way for him to flout the rules.

When he returned to the U.S., he began going to drugstores and buying pads and tampons; soon, he was writing to researchers and menstrual-product manufacturers, some of whom sent him menstrual cups or old belts, the kind that women used to wear to hold disposable pads. A one-off thought he had back in Germany—“As a joke, I was just thinking one day, wouldn’t it be funny to start a museum of menstruation?”—became a more serious idea, and then a goal, and then, after thousands of dollars and thousands of hours of work, the thing that lived in his New Carrollton basement and consumed him for nearly half a decade.

He kept his day job, opening the museum by appointment on weekends to lead tours for guests, most of whom were women, few of whom visited alone. “There were very few single women who came by themselves,” Finley said. “They usually came with someone else. Sometimes it was a man, and I always had the feeling they were bodyguards.” To give his collection a sense of authority, he assembled a MUM board of directors that included Philip Tierno, the pathologist who helped to identify a link between tampons and toxic-shock syndrome in the 1980s.

Partly in an effort to make visitors more comfortable and partly to embarrass the ones who snooped, he bought a box of tampons and put it in the bathroom cabinet, with a sign encouraging people to help themselves.

There’s only so long a guy can play willing host to strangers who are visibly uncomfortable in his presence. It’s an exhausting way to live, as a novelty even, or especially, in one’s own home. After a few years, it began to wear on Finley. He wrote to museum directors, asking them to take the collection. And then, when it all became too stressful and too frustrating, he tore the museum apart and placed all the items in storage. He decided to build a website about his collection, which he could update on his own time.

It’s impossible to talk about the life of the museum, though, without talking about the blowback—in part because Finley seems determined to make it a part of the story of MUM. On the left side of the homepage he designed, a column of reviews displayed criticism right next to praise: A snippet from The New York Times called the museum “odd, funny, and well-researched”; beneath it, Finley quoted a listener from a radio interview who called in urging him to “get a life, creep” and a letter praying for “God [to] close your horable [sic] museum.”

To hear Finley tell it, in fact, MUM is as much a triumph over the haters as it is anything else. He says bookstore clerks give him funny looks when he purchases books on menstruation, and that coworkers would call him names. One time, he told me, he received an unsolicited package from a woman in Chicago and refused to open it, convinced it was a bomb. (It was tampons.)

“If I had anything put on my tombstone, what I would like it to say is, ‘Founder of MUM, the Museum of Menstruation,’” he told me. “Of course, they would probably refuse to put it on there.”

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A lot of Finley’s angst seems to come down to a question of turf. In an informal poll of my female colleagues, no one seemed wild about the idea of a man who was enthusiastic about periods the way Finley was. “If somehow we’re talking about it, that’s cool, but if he wants to bring it up frequently …” one said. “I want a guy to be curious about my period to the extent that it concerns my well-being,” another told me. The consensus: Asking about symptoms was welcome, anything else was not.

Finley knows this. If, by his own admission, he started out by chasing a taboo for its own sake, he’s ended up in a very different place. His rebellion now comes with a sense of purpose. He talks about himself as a male trespassing in female territory, but for the right reasons.

Some people “have never talked about [menstruation], even with other women. And I saw this again and again with visitors,” he said. “People would start talking. Even people who didn’t know each other would start talking to each other …  I really felt that I was doing the right thing. I felt that I was doing something useful.”

“People assume that it’s creepy and there must be something wrong with him. And there isn’t,” said Chris Bobel, a professor of gender studies at the University of Massachusetts, Boston, and a board member of the Society for Menstrual-Cycle Research. “He’s just a lovely, curious man who found something that hadn’t been documented adequately, and he put the energy into documenting it. Good for him.”

Bobel, who has spoken with Finley about ways to raise money for a new home for the museum, thinks funding, not maleness, is his biggest obstacle. In fact, she thinks his gender may be a boon to eventually getting it off the ground.

But if the new museum happens, Finley doesn’t want to run it. “I don’t have to be the boss. I don’t want to be the boss. I understand the objections to that,” he said. He imagines his collection as a themed wing of a larger women’s-health museum, something he can support from a greater distance. “I could be a board member, and maybe have Men’s Night every Wednesday or something … If they aren’t hostile to men, if they don’t discourage men from coming in, it could be a tremendous thing.”

When I think about it—about a Men’s Night at a women’s-health museum, about my colleague’s answers, and about my own discomfort—I think of this: A few months ago, during a weekend with my boyfriend’s family, his sister asked us to pick her up some tampons when we went on a grocery run. When I grabbed a box with cardboard applicators, my boyfriend all but knocked it out of my hands.

“Those are like sandpaper,” he said. “Get the nice ones.”

In a weird way, it’s a sweet story. Here’s a guy who a) cares about his sister, and b) is mature enough to acknowledge that his sister has a vagina without making a fuss about it.

But also, here’s what I hate: that I still felt the need to preface that with in a weird way. Yes, his sister’s vagina is, conceptually, an awkward combination of words. But on the other hand, why should he care about her discomfort any less just because it happens to be in that part of her anatomy? And why, in a story about a man and a woman and a box of tampons, is the woman the one who can’t be a grownup about it?

This is what Finley believes he’s up against—people like me, who see strangeness where they should see compassion. The writer Ann Friedman may have summed it up best when she shared a recent Vice profile of Finley in her weekly newsletter: “I wish I wasn’t so creeped out by the man who runs a menstruation museum out of his basement.” She wishes. But she is.

* * *

In a note on an earlier version of this story, my editor wrote: “Is he a bridge to a better future? Or an eccentric symptom of our crappy present?”

I know Finley used to think he’s the former. I know he no longer does. I would say he’s more the latter, I guess, but even that doesn’t really seem to fit. The clueless bro is a symptom; Finley is something else, a little more tragic and infinitely more frustrating.

People talk about “reclaiming periods”—and implicit in that is the idea that there’s someone to reclaim them from. That’s Finley’s problem: In an narrative of Lammily dolls and women who bleed through marathons, there’s not a model for a male savior. As well intentioned as he may have been—and he was well-intentioned—he, not menstruation, became the taboo he was fighting against. He was always trying to tell a different story.

It’s unclear if he still wants to tell it. For a brief window earlier this week, the thousands of pages of the MUM website temporarily vanished. In their place was a note from Finley. “These were the best, most exciting things I’ve done,” it began. “[The museum] opened many eyes and minds, including mine.”

But “to avoid further nastiness,” he continued, “I’m eliminating the museum.”

He signed off: “MUM was the word!” A nod to the museum, and also an order, or a promise, to keep something quiet—it felt like a fitting eulogy.