Minamoto Kou is a middle school student at Kamome Academy and a member of the famed Minamoto exorcist clan. He is the younger brother of Teru Minamoto and the older brother of Tiara Minamoto; his surname was initially "Adashino" in the series pilot. Kou bursts with impulsive energy, often acting brashly without thinking. He sports spiky blond hair, blue eyes, noticeable canine teeth, and wears a red traffic-safety omamori as an ear piercing on his right ear. His uniform includes an unbuttoned teal shirt over a black undershirt, a cream-and-brown striped tie, and a red sweatband on his right wrist. Kou wields the raiteijou, a spirit staff disguised as a black umbrella that channels his spiritual energy into lightning for exorcisms. Its full power is sealed by Hanako, making it unreliable and prone to electrocuting Kou. He sees and interacts with supernaturals naturally. Initially idolizing his older brother Teru, Kou aspired to become an exorcist like him. Tasked by Teru to exorcise all Seven Mysteries, including Hanako, Kou failed against Hanako's strength. Interacting with Hanako and other supernaturals made Kou question his clan's belief that all supernaturals are evil. He openly defied Teru to protect Hanako, vowing to decide for himself when exorcism is necessary after gaining more strength and understanding, marking a significant shift from blind obedience to clan principles. Kou evolves from an arrogant, rash teenager into a more mature yet still justice-driven protector. His relationships fuel his growth. He harbored an initial crush on Nene Yashiro, drawn to her "cute smile." His complex friendship with Hanako evolved from antagonism to mutual trust. Kou's deepest connection was with Mitsuba Sousuke, his deceased former classmate. After encountering Mitsuba's ghost, Kou tried to help resolve his regrets, forming a strong bond. Witnessing Hanako destroy Mitsuba after Tsukasa Yugi transformed him into a violent supernatural devastated Kou, fueling his fight against evil supernaturals. This grief drove Kou to attempt suicide to stay with Mitsuba permanently, showcasing intense loyalty and turmoil. He struggles with the resurrected Mitsuba, feeling he is not the same friend. Kou handles all housework and cooking for his family, excelling at making donuts and sweet potato jellies, his favorite snack. He dotes on his spiritually powerful younger sister, Tiara. Mirai's powers during the Three Clock Keepers Arc aged Kou into an adult form resembling Teru, briefly aligning with Nene's preferences. Beneath his cheerfulness, Kou grapples with insecurity and a need for validation. He envies Teru's confidence and popularity, often feeling insignificant. Kou seeks purpose through protecting others, risking himself to prove his worth, a drive partly stemming from Teru's dismissive remarks like telling him he'd be "more helpful in the kitchen." His loyalty to friends remains unwavering as he confronts his vulnerabilities.