T’Pring (played by Arlene Martel), was a Vulcan female who was bonded to Spock as a child. In “Amok Time” (season 2 episode 5), when Spock began suffering from the pon farr, he returned to Vulcan to mate with T’Pring.
T’Pring, however, preferred Stonn (another Vulcan male) instead, and executed her right to claim kal-if-fee at the koon-ut-kal-if-fee ceremony (a Vulcan wedding). She picked James Kirk as her champion, and he accepted while being unaware that the fight was to be to the death.
via Memory Alpha