I mean The Prince and Bard have little to no relation to each other myth-wise if I recall, they also have no reason to be considered destruction classes too. Then again, you could argue with Maid and Sylph about that, although the Maid does provide and make things from what I remember.

For more specifics about the Prince-Bard relation, you should check optimisticDuelist/revolutionaryDuelist/Taz’s exposition about Princes, Bards and their connection to Royalty as the unifying myth for both.