>>49462727Hisami is one of (or the, thing with Kojiki is that it has no distinction of plural and singular form, so you need to fall back onto context and other versions of myths, which is not always conclusive) yomotsu-hisame, hags from the underworld, Yomi.
Japanese archipelago and many of its kami were created by Izanagi and Izanami, but Izanami died when she gave birth to kami of fire. She went to Yomi. After some time Izanagi came down there, seeking her, wanting to continue their creative work. Izanami asked her husband to wait and and look at her, but because the darkness was oppressive, Izanagi lit a torch and saw his wife with already rotting body. He began to run away, while Izanami, angry from shame, send yomotsu-shikome to chase after him. After quite perilous pursuit involving distracting hag(s) with food (this is why there is a grape motif on Hisami), Izanagi managed to flee from Yomi. He locked the passage to the underworld first with a giant rock, then, in order to clean himself of underworld's filth by bathing in river, Izanagi threw behind him his staff and clothes. The rock (Michi-gaheshi-no-oho-kami), the staff (Kunado-no-kami) and some of the clothes (like trousers, Chi-mata-no-kami [yes, that's Chimata]) turned into deities whose task was to ward off and stop Yomi's evil spirits, including yomotsu-hisame, from entering mortal realm. All of them were later associated with dลsojin, whom Nareko is.
So Nareko is technically person who should be responsible for preventing Hisami from unrestrained roaming and luring people into Hell. However, Nareko is definitely bored out of her mind, her Egyptian larp is a proof of that. So I can imagine scenario in which Hisami tries to subvert Nareko into another Zanmu's enthusiastic fan, with as much romantic tension as you want.
Is it far-fetched? Yeah, sure. But I think Chimi will settle as a parent/grandparent figure for Nue and she doesn't have much else, while Ubame... pairing her with Nemuno feels way too obvious, one destroys sanctuaries, other makes them and that's it? Sannyo is completely disjointed from other yamanba. If there was actual Tenma presented, we would probably see the pairing between them (two leaders of youkai that control most of Youkai Mountain), but will Megumu, as a high-ranking tengu, be used as a substitute? I doubt this, from the mere fact of Megumu already having many pairings for a relative newhu.