Whether you’re a dedicated Fritz the Cat fan, more of a Mr. Natural-type, or simply enjoy the odd perusal of his finely illustrated realm of sexual obsessions, you might know that Robert Crumb (a.k.a. R. Crumb) likes his women ample, his art nonconformist, and his bitterness self-referential.

In honor of the publicity-shirking cartoonist’s 72nd birthday, you might do well to plunge even deeper into Crumb’s squirrely, squiggly world to discover some lesser-known facts about the guy who brought underground comics into the anxious, sweaty mainstream.

1. HE DREW A VERSION OF HIS WIFE BEFORE THEY EVER MET (WHICH IS HOW THEY GOT TOGETHER).

The New York Times explained that cartoonists R. Crumb and Aline Kominsky-Crumb “met in 1971 after she heard about a large-rumped woman named Honeybunch Kaminski created by Mr. Crumb for his Snatch Comics series” who bore a striking resemblance to Kominsky. So she “set out to meet the famous R. Crumb.”

In 2007, the couple appeared onstage together as part of a Valentine’s Day event at the New York Public Library, where Aline continued the story, noting that they “first met at a party at Robert's girlfriend's house, and he told me that I had ‘cute knees.’”

2. HE PLAYS BANJO AND UKULELE IN TWO OLD-TIMEY BANDS.

The mostly string-based bands R. Crumb & His Cheap Suit Serenaders and R. Crumb and His Keep-on-Truckin’ Orchestra have been playing old-time, ragtime, folk, bluegrass, and blues music for decades, and feature classic themes but also ones that directly affect self-critical artists.

3. HE’S DONE THE COVER ART FOR SEVERAL ALBUMS (INCLUDING HIS OWN).

As Rolling Stone reported, Crumb isn’t just an avid record collector, he has also designed the covers of a number albums ranging from his band’s releases and a compilation of female singers to Big Brother and the Holding Company’s 1968 hit Cheap Thrills.

He created the latter as a “work for hire” in one night for just $600, and told Rolling Stone he enjoyed working with Big Brother singer Janis Joplin: "Janis used to come around, smoke pot, talk about the comics … She was nice." For several other album cover jobs, he has happily accepted payment in vintage records. He won’t do work for bands he doesn’t like, though—the Rolling Stones included.

4. HIS OPINION ON MOZART, SCREEN VIXENS, AND PETER SELLERS? “OVERRATED.”

A compiled list of some of Crumb’s thoughts on famous figures—targeting everyone from cinema legends to recent politicians—reveals that it can take a lot to impress this cartoonist (unless you’re his female classmate from high school). Here are a few of his takes on some highly celebrated artists:

Mozart: "The music just doesn’t do much for me. I haven’t really [paid] close attention to Mozart’s music. I love the movie [sic] Amedeus about him, but the actual music, nnnaaaah.”

Silver-screen bombshells: “[Movie stars] didn’t attract me as much as the girls in my high school class. I wasn’t impressed with women in movies as I was with the big legged girl who sat next to me in my homeroom class, Joanne Plunk. I was much more dazzled by her than any girl in the movies.”

Mark Twain:Tom Sawyer and Huckleberry Finn don’t do that much for me. But his later stuff, he gets more cranky as he gets older. His critique gets more interesting.”

Stanley Kubrick’s Dr. Strangelove: “Great movie. Great. Masterpiece. But I don’t like Peter Sellers. I think he was highly overrated in his day … I think he really spoiled Lolita. They shouldn’t have let him do his shtick so much in that film … [Lolita] could have been a great movie but Sellers f***ed it up.’”

He does like plenty of famous artists, though, including Charlie Chaplin, Laurel and Hardy, and W.C. Fields. As for Tommy James and the Shondells? "Yes! Last great proletarian rock n’ roll band.”

5. HE MADE AN (ACCURATELY) ILLUSTRATED VERSION OF THE BOOK OF GENESIS.

Crumb told The Paris Review that he took on the 2009 tome “for the money and I quickly began to regret it. It was an enormous amount of work—four years of work and barely worth it. I was too compulsive about the detail. With comics, you’ve got to develop some kind of shorthand. You can’t make every drawing look like a detailed etching. The average reader actually doesn’t want all that detail, it interferes with the flow of the reading process. But I just can’t help myself—obsessive-compulsive disorder.”

However, the artist did feel that bringing the book’s Biblical stories into vivid, Crumb-style color may have served a purpose for readers not familiar with the text:

“I think that the best public service that it has to offer is that it brings everything out. It illustrates everything equally. Even the strangest stories, stories that don’t make much sense. The Bible was not written for entertainment purposes so it’s a real hodgepodge and a compendium of all kinds of stuff."

While the underground cartoonist is not a religious man himself, he says that he “did try to be respectful. I decided not to make fun of the text, not to put any kind of jokey stuff in there. I was tempted a few times. But I whited it out later because it distracts from the text. The text itself is so compelling that merely illustrating it is enough.”

6. LIKE HER PARENTS, SOPHIE CRUMB IS A SUCCESSFUL CARTOONIST.

While her life has certainly taken its own directions (her marriage, for example, is not an open one, like her parents’), 33-year-old Sophie Crumb picked up the family pen and became an accomplished cartoonist and artist in her own right, and with a style that shows hints of the aesthetics and tones in Robert and Aline’s work.

As The New York Times explained, the Crumbs relocated to the South of France in 1991 partly “to shield [their daughter] from a growing conservative and fundamentalist Christian influence while continuing to educate her in what they consider the classics,” and instead “reared her on Little Lulu comics from the 1940s and ’50s and Three Stooges videos.”