Though one thing I have noticed during the playroom is that if you let Honeygast eat you and not struggle for a bit. The heart that would allow you to befriend ghost and add them to the "Fed" part of the ghostiary appears after long enough. Though Idk if that would count with the Honeygast. Same happened with Mitsuro (I presume the same is Mirrim though Idk if she or Mituro can be eaten)