It is an unrelated topic from this chapter, but...
I re-read this manga from the beginning, and I have a hunch that the Informant Kouhai is actually Kuzunoha in disguise.
If you think about it, the Informant gal , Mei Tachikawa, and Kuzunoha have exactly opposite traits; she is a Kouhai instead of a Senpai, cheerful and outgoing instead of stern and strict, and can openly show her affection to Haruhisa. It's everything that Kuzunoha wanted.
Mei also strangely has the same talisman that is used by Kuzunoha, and they were transformation Talismans, which is a technique the Kuzunoha clan are best at. It would explain why Mei can access information that might only be available to high-ranking exorcists.
Also, during the last arc with Sakura, Kuzunoha tricked Sakura, making her wait for her, but then ditches her. Then, in the next panel, Mei appears in Haruhisa's room. In chapter 46, Mei also somehow can recite what Haruhisa said to Kuzunoha exactly line by line. Also, so far, Mei always appears exactly after Haruhisa meets with Kuzunoha.