The main protagonist and the 'father' of Midarezaki family who originally was forced to participate in Peaceful Family Operation. Ouka can be described as sensible and collected, however, he is often teased and mocked by Kyoka. When in extremely stressful or dangerous situations, he will pull a handgun he carries, once even pulling it on himself. He is also the head of the operation department of 'Supernatural Phenomenon Treatment Bureau' ().
Ouka lost his parents at age of three, and has no memory before then. He was raised by the Bureau, and was taught not to love anything or anyone. Despite this, Ouka eventually learns to love the family he was assigned to watch over.