Post tags are kind of an unofficial thing that (afaik) only photon supports. So, posters should feel free to use tags as they wish. I can add some recommendations to the sidebar/rules though, like in !manga@ani.social. When lemmy 1.0 comes out, or if this community ever ends up needing to move to a piefed instance, there will proper post flair that can be used instead.

As for the episode discussion threads, I can modify the bot’s template to include a tag. The manga community-style tag would be [DISC] or [Discussion], but the anime subreddit uses the [Episode] flair. I don’t have a strong preference and would be open to feedback on which way to have rikka go.