The Ark Academy's transfer student, Origamine Ouka, was the homeroom teacher's childhood friend and the princess priestess of the oni clan. Though she used to be like a little sister to him, upon reuniting after several years, she witnessed him performing 'Assistance' with a student and exploded in anger. Ouka sealed the teacher's manhood with an oni spell. "You are tainted, brother." Unable to perform 'Assistance,' the teacher tried to persuade her, but Ouka was adamant. As a last resort, he decided to gently unravel her heart, which had been restrained as a princess and a priestess, with his kindness as a childhood friend and a teacher. Sweet moans unimaginable from her dignified demeanor, and her ample breasts released from her solemn kimono. What was supposed to be a sex-filled time in the absence of the oni turned into tears in the eyes of the oni! With more intense service scenes than ever, it's a golden club for the oni!