Gakushin
One of Kyosho's Three Pillared Gods, Gakushin has the unusual ability to read someone's magatama through French kissing them—a power she's put to use more than once. She's best known for discovering Kanu's hidden feelings for Ryubi this way, though the experience shook her deeply. When she peered into Kanu's mind, she didn't just learn about her romantic life; she caught a vision of Kanu's past incarnation from 1800 years ago, and what she saw left her genuinely rattled. Realizing just how formidable Kanu truly is when fully awakened was enough to break Gakushin down completely.
She's also used her kissing technique on Koukin to track down one of the Hyakuhekitō.
The anime and manga handle one key scene differently: in the manga, Gakushin reads Kanu's mind after Jokou knocks her unconscious, but the anime version has her doing it after Kanu surrenders and gets taken prisoner. It's a minor shift in pacing, but it changes the context of the moment.
Content compiled by AnimeList.moe from publicly available sources.