Akiko - A cute, shy girl in Taro's class who has had a secret crush on him for awhile. She could offer help or insight during a tense moment.
Sota - Yumi's mischievous little brother who is always getting into scrapes. He unwittingly stumbles upon clues about the supernatural battles.
Mamoru - The captain of the kendo team, he is initially suspicious of Taro but grows to respect his power and bravery. Could be a valuable ally.
Izumi - A snarky, standoffish girl with a mysterious past. During the festival attack, she surprisingly aids Taro and Yumi, hinting at her own powers/history.
Heisuke - A clever but cocky Tengu spy who brings urgent news from the demon realm about old enemies joining the samurai's cause.
Principal Tanaka - The strict but fair school head seems oblivious to the strange events but may have hidden insights as a descendant from an ancient ninja clan.