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One aspect of Zaruba that was never explained was how he ended up with Raiga. When Legendary Horror Eyrith opened portals between time and space, Kouga's wife, Kaoru Mitsuki , was sucked into the vortex. In an attempt to save his wife, Kouga also jumped in. When he appeared during to save Priestess Rekka and Rian , Zaruba was still with him, but if Kouga is lost in between realms in search of Kaoru, it questions is the current ring worn by Raiga a replica or Zaruba somehow made his way back to Raiga or it was a continuity error.