help:tag implications
Tag implications are used when all images belonging to one tag should also be tagged with another, broader tag. For example, 4koma implies comic, and fate/stay_night implies fate_(series).
Since implications are applied automatically with no way to override them, they are only used in situations where one tag is always tagged with another. Special care should be taken to consider potential edge cases when requesting the creation of an implication.
Implications are only used when both tags are of the same type (general, copyright, character, or artist). Character tags do not imply their respective copyrights, as the maintenance burden for such a system would be too high and of questionable benefit (see topic #10624).
When two tags refer to exactly the same concept, an alias should be created instead.
You can request that an implication be created using the bulk update request form.