T'Pring rejects Spock as her mate and chooses to claim Kal-if-fee in 2267.
The Kal-if-fee (which literally translates as "challenge") is a Vulcan "passion fight" to the death, in which two Vulcan males fight for the right to mate with a certain female. During the Vulcan mating ritual known as Koon-ut-kal-if-fee, a female can claim Kal-if-fee if she does not want the male arranged for her at childhood. At which point, the male arranged for her must fight the female's selected mate. (TOS: "Amok Time")
When Vorik underwent pon farr in the Delta Quadrant and wanted to take fellow Voyager crewmember B'Elanna Torres as his mate, the half-Klingon female ultimately claimed the kal-if-fee, and chose to champion herself. (VOY: "Blood Fever")