Who is the character who show up from time to time to comment?

The character you're referring to is likely the "narrator" or "commentator" in various forms of media, such as books, films, or television shows. This character often breaks the fourth wall to provide insight, humor, or commentary on the events unfolding in the story. They can serve to engage the audience more deeply and add an additional layer of interpretation to the narrative. Their presence can vary in frequency and style, depending on the work.