Black and white
After Kerrigan refused to repeat the psychic attack that had harmed her father, Lieutenant Rumm provided her with a kitten injected with a tumor. She was informed that the tumor would kill the kitten slowly and painfully unless Kerrigan either removed the tumor, or put the kitten out of her misery. Kerrigan refused, even as Rumm pointed his pistol at it.
Kerrigan refused to do either, and Boots lasted three weeks before succumbing to the cancer. Kerrigan's decision to let Boots suffer rather than give into her tormenters haunted her for years.