What does Callista mean?
From Greek kallistos/kallistē 'most beautiful', the superlative of kalos, from kallos 'beauty'. Kalliste was a title of the goddess Artemis; the mythological nymph Kallisto bears the same root.
What does Pandora mean?
From Greek Pandora, combining pan 'all' + doron 'gift', meaning 'all-gifted' or, by an older reading, 'all-giving' (giver of all gifts). The scholarly sense is disputed between 'gifted with everything' and 'giver of all'.