Sorry if being a lurker and new to Kirai (play The Vikis mainly), but being a game tester and rules and toruney ref for a number of other systems, there is a rule "bending" that I see as potential though fun problem.
RAW - Kirai Spirit Anchor, "When a living, spirit or undead model is killed....." Seishen is a spirit,
A B2B Seishen is "killed" taken the wounds for Kirai, where upon due to the Play rule a new one is "placed" on the board. in effect that means that the Sesihen is in effect never removed from play (as you'll be replacing it in B2B from the one that was already there and thus have the space). And thus Kirai will effectivly take no wounds..
Sorry if I miss read but still see this a potential game (encounter) bender - lol