Inseki works more for a non blood related close relationship, even more, for daughter in law there's the term "Gifu" which is totally different to "musume", i think we seriously need a clear separation to avoid getting unwanted results in the tag system seach method.
@Metrascope It will help to filter out the two inseki tipes as the relationship dynamics are very different one is by adoption the other is by marriage
I think inseki already evelops both in-laws and step relationships.
This tag feels kinda too specific when you can get this same result with like, 4 to 5 search terms