This category contains characters, divided by how important they have been throughout the series. It is first divided by importance, then by human/animal if necessary. "Meaningful" in this context implies greater importance than making a simple cameo. "Significant" in this context implies direct involvement in a plotline.
"Protagonists" indicates characters that have been present for a minimum of 70% of episodes since their debut episode (in production order). "Secondary" refers to characters that have appeared in at least 8% of episodes since the season of their debut, with at least 5% of the total episodes since debut season being significant. "Recurring" refers to characters that have appeared on multiple occasions and have had at least two meaningful appearances. "Minor" refers to characters that have only cameos and/or one meaningful appearance.