Menace of the Twins

Two sister queens who fight for the thrown. One of them turned down the wrong path and became The Queen Of Tenebris or darkness. The other followed her mother's footsteps and became The Queen Of Bonitatem. or goodness. During this fight to death one of them develops an illness that can be cured only by the blood of her twin. True love is found by the one least expected and a tornado decides to storm through one of their castles and shred it to ruins.