Short but sweet, in a melancholy way; the attention given to the music, and to the border that frames the game like the margins of a storybook or a medieval illustrated text, really created an enchanting atmosphere! The idea of a "cage cup" is intriguing, and the game seemed like a brief glimpse into a much wider world.
Ending-wise, though I got both, I did the "Destroy" ending first and feel as if it's the correct one, at least for myself: There's no guarantee of being able to undo the curse, the rest of the clan is dead and there's no way of knowing if Fergal's brother could ever be freed. Additionally, there's no hint that the viewpoint character is immortal, meaning I can't promise that the cup won't end up lost or forgotten, leaving the brother alone and possibly mad from solitude for eternity. Either way, the story outlives its characters. Nice job!