Iwanaga Kotoko has a very cool job, a job I would love to have. This week, she’s summoned to a very fretful giant serpent guardian spirit of a swamp on Mt. Tsukuna. This serpent needs the calming, ironclad explanation for why a woman dumped a corpse into his swamp and said to herself “I hope they find you.”
Kotoko probably doesn’t expect this to be a dangerous mision, and this is confirmed when the serpent expresses his general distaste for humans. Her reason for inviting Kuro to tag along isn’t about protecting her or defeating a boss, like last week’s case. So what is it about?
I’d say it’s a combination of her genuine affection for him and desire to be his wife, and part of that if the Goddess of Wisdom can become involved with the human most youkai fear most, perhaps she can show them he’s not really so bad!
That said, she’s unable to convince him to accompany her to Mt. Tsukuna, though when she uses youkai to locate his apartment, he sends her off with a hoodie to keep warm in the mountains and a hot meal of miso soup and onigiri, so he doesn’t come off as completely heartless.
Also, unbeknownst to Kotoko until much later in her meeting with the serpent, Kuro actually does follow her and observe from a distance, perhaps trying to get a feel for who this person is without the benefit of her being able to put on any airs.
What he witnesses is a surpassingly clever and well-spoken young woman who not only shows the serpent spirit respect and deference he doesn’t believe he deserves, but holds his proverbial hand through all the facts of the case she has amassed with the help of the youkai who work with her.
As the serpent attempts to rebut Kotoko’s explanations, Kotoko simply zigs or zags to a new route, adding ever more color and depth to the story of what led to Tanio Aoi dumping Yoshihara Hiroo’s corpse in the serpent’s swamp.
Since Aoi lived at the foot of Mt. Tsukuna, she may well have been aware of the fact the serpent was once worshiped there as a water god who brought rain. While the serpent betrays a bit of godly haughtiness by saying he would have much preferred a beautiful living girl to a dead middle-aged man, Kotoko reminds him there are two ways to bring rain: presenting an offering to please the water god, and one to enrage him; Aoi did the latter.
That’s when the youkai Kuro used to track Kotoko reunites with its sibling, and Kotoko realizes Kuro has been there all along listening in—including the part where she called him her boyfriend. But before their “lovers quarrel” as she calls it, she wants to resolve all lingering questions and doubts the serpent might still have. Not only does she have a cool job, she knows it, and thus does the very best work she can.