Sibling Rivalry

He is the savior, the prophecies foretold,

to salvage his kingdom out of rotting fold.

He is the hero, the valiant, who the people adore.

She is the enchantress, the witch, others say whore.

With guidance and love, he rules the Stonehenge.

Abandoned by her own mother, she plots her revenge.

A/N: Can anyone guess which siblings I speak of here?