How would you describe the duke? Is he a reliable narrator?

My Last Duchess BY ROBERT BROWNING; Launch Audio in a New Window

How would you describe the duke? Is he a reliable narrator? How does the title of the poem affect your understanding of the duke?

Note: An unreliable narrator refers to a narrator that the reader shouldn’t or can’t trust entirely. The narrator’s description of events might be incorrect or tinged by their experience. They add to the overall story through their biased, compromised, or simply incorrect understanding of the story.