In 2020, Justine Tiu turned her hobby into a full-time six-figure business.

A former Google Classroom software engineer, Tiu started crocheting to unwind while engaging her brain after work. After realizing its appeal, she and her husband Adrian Zhang — an ex-Wall Street director — spent $200 on yarn and a domain name to launch The Woobles, a crochet kit company.

On Friday's episode of ABC's "Shark Tank," the pair told investors just how broad the hobby's appeal really was: The company had brought in $3.1 million in revenue in just the past year, and $5.3 million in lifetime revenue since launching two years prior. All five Sharks quickly decided they wanted a piece of the company — and showed they were willing to betray their business partners to get it.

Ultimately, Tiu and Zhang left the show with a $450,000 investment offer from Mark Cuban and Lori Greiner. In return, Cuban and Grenier split 6% equity in The Woobles, which was on track to hit $7 million in annual revenue at the time of filming.

Kevin O'Leary was the first to make an offer. He wanted 10% of The Woobles for $250,000 and promised to reduce the company's customer acquisition costs — which were $16 per customer — by at least 8%.

Barbara Corcoran quickly followed, upping the deal to $300,000 for the same amount of equity. Greiner made the same offer, asserting she was a better Shark to partner with. She said she had the most experience to help Tiu and Zhang achieve their goals — to gain licensing on well-known characters and enter wholesale markets.

A bidding war began. Corcoran increased her offer to $350,000 for 10% of the company. Greiner countered with $300,000 for 8%. Corcoran responded by offering $350,000 for 5%, which was $100,000 more that Tiu and Zhang had initially asked for.

"That's how much I believe in your business," Corcoran said. "You are sitting on a rocket. But have to let me know right away because I'm being a fool here, bidding against myself."

Tiu and Zhang said they liked the offer, but would be more inclined to accept if another Shark joined the deal. Corcoran extended the invite to Cuban, who accepted. The pair now asked for 6% at $350,000.

Greiner insisted her offer was better because she could get expand The Woobles reach by herself. Tiu and Zhang said they thought her experience fit their company's needs, but once again asked if she'd be willing to add a partner.

Herjavec volunteered, and with Greiner, increased the bidding to $450,000 for 6%.

Tiu and Zhang conferred, then countered with an unusual request: They wanted to strike a deal with Cuban and Greiner instead. Cuban leapt at the deal: "You guys are as Sharky as we are!"

The couple accepted, leaving Corcoran dumbfounded. Tiu and Zhang left the tank with two prominent business partners and a $450,000 investment deal, while only giving up 6% of The Woobles. And, as Zhang said: It turns out Cuban and Greiner were their target from the beginning.

"It was definitely a risky move to try to break up Barbara and Mark and get Lori in there instead," Tiu said. "But we're glad it worked out."

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

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