The current head of Hakanoin House, one of the six houses of generals: Koga, Nakanoin, Rokujou, Iwakura and Chigusa. These houses are handling the country's military affairs. He is a very prominent figure because the current head of Koga House, which is the leading house out of the six, is a woman with strange ideas who is treated as an exotic beast. Actually, it may even be said that he is the most influential figure among the houses of generals. He is an ambitious, talented, cold-blooded, and competent man, who will stop at nothing to achieve his goals. His love is the current head of Koga House, Koga Rindou Suzuka, who does not reciprocate his feelings. Reizen took Mibu Soujirou as a vassal and made him participate in a Fencing Kagura ceremony. Also, he played an important role in the Eastern Expedition, assisting Koga Rindou Suzuka and, when she was unable to command, taking command of the army himself. In the Eastern Expedition, in the Suwahara, Reizen met a peculiar Tenma, who he deemed as an Observant. After that, something began to crumble inside him. Changes started to appear within him. Slowly but surely, his already strong ego has begun to rise, and in the end, his mind has come to the idea that others are not needed. He became obsessed with the Hajun. He sent troops to get rid of Sakagami Habaki, Mikado Ryuusui, Mibu Soujirou and Kyougetsu Keishirou. The heads of the Iwakura, and Chigusa Houses were killed by him. In the end, Reizen has almost ceased to be himself, confusing himself with Hajun. At the end, he was able to free from the obsession thanks to Sakagami Habaki, but it was too late.