Good Vampire rewarded with the Cure for Vampirism.

I was also surprised when my vampire sim, Hal, achieved the Good Vampire aspiration and was rewarded the cure. However, like you I had no intention of using it. In my world there is no cure for vampirism and watching everyone else die around you is part of the tragedy of being a vampire/immortal. What makes Hal 'human' is the desire to be human, not whether he has fangs or not, and I'm sure it's the same for Caleb. I love vampires though.