While Don Juan is the titular character, I feel that the main character is not him, but the narrator. Not only does his strong personality (reminiscent of Byron’s) color the events of Don Juan’s life in the eyes of readers, as his word choice indicates his feelings towards Don Juan and his family, but he regularly inserts his own opinions. Early on, it is short interjections, like in stanza 60 when he says he appreciates “handsome eyes.” Moreso, though, the end of Canto 1 just includes the narrator’s opinions on epics, on contemporary authors like Coleridge and Wordsworth, love, education, and generally life–and these opinions line up in a way that is more than coincidental with Byron’s own. Don Juan isn’t even an afterthought; he is simply not mentioned. The narrator is the driver of Don Juan’s story (deciding the order in which to tell it as well as the manner of conveying it), but the poem can continue without Don Juan. The narrator seems like Byron’s explicit way of presenting his own opinions, which might be why the epic can continue without any (other) characters.