>>3044069I was going to post Kira next but her fanart is way too low quality, so here's Wakaba and Terazuma. Wakaba appears twice in the anime with some lines, while Terazuma can be seen for a split second in the OP, and his back for a few seconds in the last episode. They're the most OTP and the mangaka's assistants made some cute doujinshi.
Even though Terazuma and Tsuzuki hate each other, he and Wakaba are good friends and hang out all the time. Aside from summons she also acts as one of the miko who open the gates to Gensoukai, and is the reason the tengu take ikemen forms. Terazuma is possessed by an angry monster that is allergic to girls and traps and Wakaba is the only one who can seal it.