ST. CHARLES, Mo. — In January 2013, a white male college student in Missouri noticed a profile on a gay mobile hookup app for a black guy with ripped abs and a chiseled chest with the username "Tiger Mandingo."

"I am more into white guys, but I like black guys," the student told BuzzFeed. He connected with Tiger because he was "gorgeous, he had great legs, and he was well-endowed."

The student at Lindenwood University in the St. Louis suburb of St. Charles quickly recognized that in real life, Tiger Mandingo was also a student at his school: Michael Johnson, a recent transfer student on Lindenwood's wrestling team. They hooked up later that month in Johnson's dorm room, where, the student said, Johnson told him he was "clean." He gave Johnson a blow job.

Johnson invited him to go out sometime, but the student got busy and "didn't have time for that." They didn't hook up again until early October.

This time, they had anal sex without a condom. "I let him come in me," the student said. He wanted bareback sex, he said, because Johnson was "huge," "only my third black guy," and — as he said Johnson told him yet again — "clean."

The student said he has barebacked with multiple "friends and ex-boyfriends," situations in which "we trusted each other. I mean, I don't just let anybody do it." Yet he also said he had bareback sex "with people I barely knew." In those cases, he said, "I knew they were clean," sometimes just "by looking at them."

The student's nonchalance changed when he described a call he got from Johnson a few days after their second hookup: "He calls me and he said, 'I found out I have a disease.' And I asked, 'Is there a cure?' and he said, 'I don't know.' And I was like, 'Are you fucking kidding me?' I got pissed. I had asked him several times, and he'd said he was clean, and I trusted him! And I got mad at him, and then he got mad at me for getting mad, and then he said, 'I gotta go.'"

That same day, Oct. 10, Johnson was pulled out of his class and led away in handcuffs by the St. Charles police. He was later charged with one count of "recklessly infecting another with HIV" and four counts of "attempting to recklessly infect another with HIV," felonies in the state of Missouri.

Johnson has pleaded not guilty. His lawyer, public defender Heather Donovan, allowed BuzzFeed to interview Johnson in jail with her present, under the condition that he not answer questions about his case. Asked later to respond to a detailed list of points raised in this article, including whether Johnson always disclosed his HIV status or ever had intercourse without a condom after learning he had HIV, Donovan wrote that "neither Michael and I feel comfortable answering [BuzzFeed's questions] at this time since his case is still pending."

News of Johnson's arrest, coupled with reports of more than 30 videotaped sexual encounters on Johnson's laptop, rocked St. Charles and lit up local broadcasts and international headlines. It's been erroneously reported that Johnson has also been charged for making the tapes, but he hasn't. The videos, like the sex acts themselves, might have been consensual. Julie Vomund, spokeswoman for St. Charles Prosecuting Attorney Tim Lohmar, wrote to BuzzFeed that the "St. Charles County Cyber Crime Unit is still working to fully review the videos to identify the people involved and at this time we have not determined if those on the video gave their consent to be filmed… there is still the possibility in the future to amend charges with additional counts."

Lindenwood University urged anyone who'd had "intimate contact" with Johnson to get tested for HIV, and many did. The student Johnson had sex with went to St. Louis Effort for AIDS for an HIV test, which came back negative, as did subsequent tests. He didn't press charges himself. Still, he said, "he infected someone with HIV. Without medication, that person could get AIDS, so he's slowly killing someone. It's a form of murder, in a sense. I hate to say it, since he's a nice guy."

With few exceptions, judgments around the internet concurred: Johnson was a predatory "monster" who was intentionally "spreading HIV/AIDS." A typical comment on Instagram proclaimed him the "Worst type of homosexual: a strong one with HIV." Overtly racist blogs, like Chimpmania.com, labeled him an "HIV Positive Buck."

The only question more important than how Johnson became both a media flashpoint and morality tale is why. The nasty racial tone the story took is not surprising, given Johnson's charged nickname, his white sex partners, and research in Tennessee that shows the law punishes black men more often (and more severely) for HIV-related sex crimes than it does white men.

Clearly, failing to tell one's sexual partners that one has HIV is irresponsible and unethical. But even if that's what Johnson did, he is hardly the only one keeping such information to himself. A 2004 article published in the medical journal Topics in HIV Medicine reviewed 15 studies on disclosure conducted over a dozen years in the United States. It found a wild variation in how often HIV-positive people disclose their status to partners, ranging from as much as 89% of the time to as little as 42%. A 2012 study published by AIDS Care found that 69% of HIV-positive gay men disclose their status to their sexual partners.

Then, too, many people with HIV simply don't know they have the virus. In 2011, the federal Centers for Disease Control and Prevention found that among young gay and bisexual men aged 18 to 24 who were infected with HIV, less than half knew that they had it. Johnson's partners also carry responsibility, because relying on someone to say they are "clean" is a foolhardy strategy to avoid contracting the virus.

This is a message that a college — a place full of young and sexually experimenting students — needs to drive home, repeatedly. Yet, while Lindenwood University facilitated HIV testing, it conducted little education on how to avoid getting the AIDS virus in the first place.

Indeed, the community around Johnson — his sexual partners, many of his fellow students, and his university — turned a blind eye to HIV until it had the perfect scapegoat: a gay, hypersexual, black wrestler with learning disabilities who went by the nickname Tiger Mandingo.

But up until his status became known in a very dramatic way, Johnson's body had been quite popular, for a myriad of uses, in that very community. As Carolyn Guild, the prevention director of St. Louis Effort for AIDS, put it, "Everyone wanted a piece of him, until he had HIV."