I was thinking of having a subplot where Anaka's body is destroying itself as she stays in the realm of the dead, basically becoming a dead person herself. (It's a lot like the real world, only people don't change much and they can't die. Oh, and way more happy sunshine.)
Ayame would do all he could to make sure Anaka came back to his plane of existence, so he'd hire someone who can
A) Break through the barrier between the planes and communicate with the 'spirits.'
B) Move through different planes of existence without taxing themselves too much.
C) Remove a 'spirit' from 'heaven' and place it in a host body.
So, yeah. Either I find someone who fits that, or the subplot needs reworking.
(The only one I could think of was Kotodama. Overseas would be better, though.)