The way we make—and spend—money is never quite as straightforward as it seems. It can be emotionally charged and complicated, a source of guilt or empowerment; and methods for bringing in cash can be traditional or, for some women, very creative. In our latest installment of Honest Accounts, a video series in which we ask real women to detail the many ways they make and spend money, we asked a 21-year-old college student in New York City to break down her $40,000 yearly income. A significant chunk of her income? Selling her used underwear on Craigslist.

As for most students, she tells Glamour in her Honest Accounts video, her income is a hodgepodge of side gigs—waitressing, working retail, dog walking—that varies from month to month. But the largest single line item is a little more unusual and incredibly fitting for a college senior graduating with a degree in entrepreneurship. In a lucrative month, she made $1,700 selling her lightly used underwear and socks on Craigslist, cashing out at $120 per pair.

Her kinky cash stream gets more interesting from there. She has a keen eye for income-growth opportunities in the world of Craigslist fetish: Extended wear will cost clients extra, as will selfies. But her biggest cash bonus was even more personal. "After one of my regular underwear clients opened up to me about his armpit fetish, I made an extra $500 bucks by allowing him to smell my armpit," she says. "We met up and I was pretty much fully clothed, and I just let him smell it for like 15 minutes."

For the financially curious, the profit margin on her "dirty-underwear business" is insanely high. After realizing the Internet is filled with women selling their used underwear to a hungry market of people with fetishes, she decided to get in the game. In one month, amid more mundane purchases from Uber Eats and Drybar, she spent $37.87 at Target to buy underwear in bulk. At only a dollar or two a pair, that translates to a massive profit with each kinky sale, which is helping to fund her own budding lingerie business. "To be honest, selling my underwear has made me feel really empowered because I'm in control of my body," she says. "It feels really awesome to be able to provide a healthy outlet for people with these fetishes."