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Mainstream trans narratives tend to emphasize disgust with one’s body as the defining aspect of the trans experience. But Lou Sullivan, a trans man born in 1951, was driven by another, less appreciated force than suffering. In his journals, published this week by Nightboat as We Both Laughed in Pleasure: The Selected Diaries of Lou Sullivan, the strongest impetus for his transition is, as the book’s title lets on, pleasure: He loves being masculine, he loves men, and no other way of existing ever makes sense to him.

Today, Sullivan is remembered‚ and beloved, for his substantial activism and for his trailblazing role as a public, prominent gay trans man. He founded support groups and created a guide for people like him, wrote a biography of an arguably trans figure from the early 20th century, and shifted trans health care practices by persuading an array of influential doctors to stop considering sexuality as a factor when assessing their patients’ eligibility for treatment. His existence undermined the antiquated notion that all feminine people like men and all masculine people like women, and his visibility advanced the ongoing effort to liberate trans people from the requirement to aim for rigid, normative gender ideals. But to consider him only in terms of his historical significance would be a disservice to the delicious experience of reading this book, which is ripe with mirth, confusion, lust, despair, hope, and charm.

"They told me at the gender clinic that I could not live as a gay man, but it looks like I will die as one.” — Lou Sullivan

As a kid, Sullivan is exuberant, eccentric, and horny. From his earliest entries, he shows an acute sensitivity to his own cravings and preferences. He exhibits not a distaste so much as an ambivalence toward the usual trappings of womanhood. “My second day of menstruation,” he writes in an early entry. “I love it!” (“Menstruation isn’t such a big, hairy thrill to me anymore,” he notes immediately afterward.) His future boyfriend, he fantasizes, “will be very thin and irresponsible, but he will love me deeply, and I him.” His attractions often blend joyfully and unselfconsciously with his aspirations. “Paul-Ringo-Paul-Ringo they keep bouncing around in my head,” he writes during a fit of Beatlemania. “They’re so perfect. Model yourself on them + you’ll have no worries.” He sees Tiny Tim on television and finds him “beautiful.” His mother scolds him for waving at a man on a motorcycle. For a phase, he commits to a Bob Dylan persona, affecting his folksy speech patterns. At a Penney’s with his mother, who has just bought him a guitar, he asks her if the store also sells “those ‘unmentionables’ meanin the cowboy boots.” He slips a pair on “just outa curiosity” and takes a strut in them, and she offers to buy them. He covets them—that night, he worries that when he wakes up the next morning they won’t be there.

After graduating from high school, Sullivan stops wearing nylons and carrying a purse, and he moves in with J, the first of his long-term partners. At first, they make a sweet match: J seems not to mind Sullivan’s masculinity at all and gamely lets Sullivan drape his jewelry on him during sex. As with Paul and Ringo, Sullivan is drawn to J’s soft masculinity while also idolizing it. “I wish I was J—he’s such a lovely male,” he writes. In all of his relationships, he offers his boyfriends more tenderness and devotion than they probably deserve—J is increasingly conflicted about Sullivan’s gender-nonconformity and what it might say about his own latent appetites, and he inflicts his shame on him. J flirts with men but refuses to acknowledge it directly. “I wish he’d admit to me he’s gay,” Sullivan writes. “It’d really turn me on.”

Sullivan’s sexual experiences around this time—he and J fall haphazardly in and out of monogamy—take on an air of freedom and experimentation. After a Lou Reed concert (from whom Sullivan will later take his name), he sleeps with a man with glitter in his long, curly hair, “wearing a red velvet jacket, his naked chest all smooth.” As his appearance continues to shift, gay men start to see him as he is: one of them. He confesses to his diary that he has always imagined himself as a boy in bed. When his identity begins to crystallize, J tries to persuade him not to transition.

I wish I could tell you that, once Sullivan realizes who he is and what he wants, he eschews his disappointing boyfriends, modifies himself as he sees fit, and rides off, self-actualized, into the leather bar. But this is no rotely inspiring trans memoir. Sullivan’s transition is nonlinear; at one point, he starts wearing dresses again, convincing himself it’s better this way, but then writes, “I continue to feel more like part of the human race, yet less like a person.” Even as he comes to gain a firm confidence in his maleness, he is vulnerable to caustic appraisals of his body by his doctors, the men he sleeps with casually, and the men he shares his life with. He is not fully immune to their bad ideas; he is a flawed, optimistic protagonist.

In Sullivan’s mid-30s, fresh out of another troubled relationship and seemingly approaching a version of contentment with himself, he is blindsided by an AIDS diagnosis. In the remaining five years of his life, he believes each year will be his last, and his sense of purpose is invigorated. This is the period in which he finishes the biography he’s been writing, ramps up his activism, and solidifies his legacy. His prose is still pithy. Paradoxically, his status gives his identity more legitimacy to those who might have questioned it before, which he coyly exploits. He often recites versions of his favorite quip: “They told me at the gender clinic that I could not live as a gay man, but it looks like I will die as one.”

I will save the details of his deteriorating health for those who read the collection in full, but suffice it to say I got through them tearfully. Like a lot of transmasculine people who have encountered his story, especially those of us who are attracted to men, I have a rabid affection toward him. I imagined him alive today, nearly 70—maybe patchily maintaining an Instagram account, maybe turning up to speak on a panel now and then, maybe cohabiting with the lifelong partner he always wanted—and I mourned him.

Before I read the diaries, when I only knew about the major bullet points of his life, I was astonished by the idea that anyone could parse his own mysterious needs so clearly with no template. I thought of him as heroic, almost inhuman. But We Both Laughed in Pleasure is better than the sterile document I had imagined: It gave me the rare, uncanny experience of reliving my youth through his, of cataloging his moments of idiocy and bliss as though they were my own, with a specificity I didn’t know was possible. After Sullivan speaks for the first time, by phone, with another trans man, he writes, “I felt very masculine talking with him, and very relaxed, like for the 1st time I was talking with someone who understood what I meant.” I couldn’t help but feel the same way.

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