User blog comment:IamJakuhoRaikoben/Chapter 422: Orochi's Fin, Review./@comment-5268982-20150302165932/@comment-5268982-20150302204223

For me it depends. If she NEEDS to have the Spirit summoned to use its powers, then I'd say it is part of her Holder Magic/Summoning.

Forgot to mention how disturbing I think the cover is :/