A young boy, Dryden, in an ancient era has set off to find his sister, Rin, who was spirit away, by rigging up some bones as armor to fight the spirit that captured her. But instead of a tearful reunion the girl claims they have never met and the two are immediately attacked by another powerful spirit. Dryden wakes up to find the girl had saved him although she still draws a blank on her memory, and to make matters interesting, thanks to his unique choice in equipment the boy has been mistaken for a spirit himself.
That combine with rogues, royalty, and a sisterhood or priestesses hailing the 'BoneSpirit' as some new deity, the road home just got more interesting​