Theron, 34, took part in a live auction during a gala for the charity OneXOne in San Francisco on Thursday.
And while she was initially selling a 2010 trip to South Africa that included World Cup tickets, a safari and a meet-and-greet with Nelson Mandela, she raised the stakes when bidding stalled at $37,000, far below the $280,000 Jeremy Piven had just raised. "For f--- sake! You can do better," she told attendees. "There is no way I am leaving here with Jeremy Piven getting a higher bid. I've got t---- for God's sake."
To sweeten the pot, she offered up a seven-second kiss for $130,000 to a male bidder. "Swine flu is going around. This is high risk kissing!" she told him.
After one man bid $135,000, a woman upped the stakes to $140,000, ascending the stage for a 20-second smooch as the audience counted down.
Theron is in a long-term relationship with actor Stuart Townsend, 36. "My boyfriend is not here tonight," she joked during the auction.