Mary Gui says she's always had a passion for fashion. The world of pharmaceutical marketing, where she worked full-time, was far from it.

So she decided to leave her job, launching a fashion blog that eventually led to the creation of Sock Candy, her Los Angeles-based company that sells sheer socks with bright patterns. It brought in just over $1.25 million in 2024 revenue, including more than $375,000 in profit, according to documents reviewed by CNBC Make It.

More recently, Gui appeared on Friday's episode of ABC's "Shark Tank," earning a verbal investment deal with millionaire entrepreneur Barbara Corcoran.

Gui, 36, immigrated to the United States from Beijing at age 7 with her single mother, she says. Her mother pushed her to pursue a stable career, so she studied marketing in school and worked at "really big" advertising agencies, she adds.

"I had also tried to apply to fashion jobs during this time, entry-level fashion jobs [and] advertising agencies that had fashion accounts," says Gui. "I just never heard back from anyone, probably because I didn't have a fashion degree or anything on my resume to indicate that I would be a good fit."

Unfulfilled with marketing, she decided to quit and run her fashion blog, called Layers of Chic, full-time in 2016. "It was really, for me, sort of like a Hail Mary," she says. "I don't know how else to get into the fashion industry, other than trying to pursue fashion blogging."

On her blog, which made money "mostly through sponsored posts," Gui posted about her daily outfits — and readers commented on her "cute" and "fun" socks more than anything else, she says.

In 2020, she founded Sock Candy, working with three freelance designers to create 10 different sock patterns. The company sells those socks on its website, and sends additional inventory to more than 300 brick-and-mortar boutiques across the U.S., says Gui.

Each pair of socks costs Gui around $3 to manufacture at a Chinese factory, and sells for $18, she noted on "Shark Tank." Sock Candy's profit margin and Gui's backstory drew the interest of the show's investor judges.

"It's an impressive business, but more importantly, you're so impressive and your story," investor Robert Herjavec said.

Gui asked the investors for $150,000, in exchange for 5% of Sock Candy, and expressed a desire to get her socks onto shelves at Target. Herjavec, Mark Cuban and Lori Greiner all declined to make offers, saying there were better matches among the show's judges for her.

The remaining investors, Corcoran and Kevin O'Leary, each said they could help Gui. "I would guarantee you that I would get you into Target," Corcoran said. "You can keep the money if I don't, and you could take your stock back."

O'Leary offered Gui $150,000 for 12.5% of the company, and Corcoran offered $150,000 for 15%. Gui asked if Corcoran would take a 10% stake, and Corcoran agreed.

Post-taping, the deal hasn't yet closed, Gui now says. The import landscape has also changed: Since the episode filmed in September, the U.S. has placed placed a total 145% tariff rate on imported Chinese goods, causing panic for many of the American businesses that manufacture their goods in China.

Gui says she'll keep working with her Chinese manufacturer, and potentially combat tariff costs — at least partially — by switching from shipping by air to a slower, less expensive freight option. Sock Candy will absorb all remaining costs for the time being, she adds.

"It will require us to plan a lot more ahead in terms of inventory and restocks," says Gui. "It's not ideal, but it's not the worst thing ever [for Sock Candy]."

Disclosure: CNBC owns the exclusive off-network cable rights to "Shark Tank."

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