Everything has settled down for Mirai now that her issues with Sakura have been resolved (so much so that the two now effectively act like sisters around one another), and with news spreading that the Calm is on its way, surely there's nothing left to be worried about?
For a Spirit World Warrior like Mirai this is perhaps true, but the impending Calm is problematic for others, marking a period where youmu's powers are significantly weakened, in turn creating a kind of "open season" for those who seek to hunt them down in the hope of the riches defeating them could bring (although as any good wolf goddess will tell you, a surfeit of youmu being cashed in would cause the market to crash). Perhaps more prescient here is what effect this even will have upon Akihito given his half-youmu, half-human genetics - unfortunately, the answer is that nobody seems to know.
It appears that there's more than just good, honest youmu hunting being planned to coincide with the Calm however - Miroku Fujima in particular seems to have a plan that he's determined to carry out, and it's becoming increasingly clear that Akihito is an important part of it. To get a hold of our protagonist however, he's going to have to make his way past some powerful opponents who are determined that Fujima won't be allowed to lay a finger on his current quarry.
Although it loses its way a little when it reverts to it fan service elements or simply tries to cram too many elements and plot points into too short a space of time, Beyond the Boundary does at least feel as if it's building towards something quite interesting here having positioned things where they seemingly need to be to provide some compelling narrative and big revelations. Provided it can live up to that potential then this could actually be an opportunity to get a real look at the strengths of the series - something that we sadly haven't been able to do anything like as much of as I would have hoped up to this point.