Ōtsuka Ryūnosuke Taira no Masatomo (大塚龍之介平政智) is the 7th Sōke of the Hokushin Ittō-ryū Hyōhō and leads the school in this generation.

Ōtsuka Ryūnosuke was born as Lösch Markus in Munich, Germany. Since his early childhood he was fascinated by martial arts and Japan. In order to completely dedicate on learning the usage the Japanese sword, he even quit his longstanding training with the English longbow, where he used to shoot bows with a draw weight of up to 130 lbs. At that time no traditional Japanese sword-fighting school (koryū) was present in Munich or its vicinity, so he first started modern Japanese sword-fighting and Musō Shinden-ryū, a modern style of sword-drawing (iaidō). Since he was not satisfied with the teachings of those modern martial arts, due to their lack in practical application, he decided to go to Japan and train in a real koryū.

In Japan he soon became a student of Menkyo-Kaiden, Ōtsuka Yōichirō Taira no Masanori in the Shinmeikai-Dōjō of the Hokushin Ittō-ryū. Due to his quick grasp of techniques and exceptional devotion he was accepted as an uchi-deshi (private pupil) of Ōtsuka Yōichirō. From that moment on he spent his time daily training in the Hokushin Ittō-ryū for several hours, which enabled him to quickly improve his techniques and become proficient in the Japanese language.

When he returned to Germany he received permission by Ōtsuka Yōichirō to start a Dōkōkai (training group) in Munich that quickly flourished. After he mastered all techniques and the philosophy of the Hokushin Ittō-ryū, he received the Menkyo (Chū-Mokuroku), 4th of the five scrolls of Hokushin Ittō-ryū, in January 2013 from Ōtsuka Yōichirō. Alongside the Menkyo he also was given a Dōjō-Mokuroku (license to open an own dōjō).
In July of 2013, Ōtsuka Yōichirō was appointed as the 6th Sōke of the Hokushin Ittō-ryū Hyōhō by Chiba Hiroshi Masatane, the 5th Sōke. The enbu, which preceded the appointment of Ōtsuka Yōichirō to the 6th Sōke, was performed by the latter together with Ōtsuka Ryūnosuke. After several successful duels he was furthermore appointed as Saikō-Shihan (highest Shihan of the school) in October of 2013.

On the 12th of July 2014 he mastered the highest teachings of the Hokushin Ittō-ryū and subsequently received Menkyo-Kaiden (Dai-Mokuroku), the highest master license, from Ōtsuka Yōichirō. In addition, he became the foster-son of Ōtsuka Yōichirō and was honoured by being given the name Ōtsuka Ryūnosuke Taira no Masatomo. Also in the same month Ōtsuka Ryūnosuke was able to rent a new location, dedicated for the Chiba-Dōjō in Munich. After the completion of the renovation and redecoration of the dōjō, Chiba Hiroshi Taira no Masatane, 5th Sōke of the Hokushin Ittō-ryū Hyōhō and current head of the Chiba family, visited and inspected the new dōjō, in spite of his advanced age.

On 26th of March 2016 Ōtsuka Ryūnosuke was officially appointed as the 7th Sōke of the Hokushin Ittō-ryū Hyōhō by the 6th Sōke Ōtsuka Yōichirō. The ceremony took place in the Nakano Sunplaza-Hotel in Tōkyō. Ōtsuka Yōichirō decided to pass the school to Ōtsuka Ryūnosuke, due to his “exceptional abilities with the sword, his deep philosophical and historical knowledge and his excellent teaching abilities”. Furthermore, Ōtsuka Ryūnosuke then became the first non-Japanese Sōke of a Koryū in the history of Japan.

Ōtsuka Ryūnosuke lives with his wife Tomomi, who studies the school from her husband, and their son Ryūichirō in Munich and personally runs the Chiba-Dōjō there. Being the successor of Chiba Shūsaku he spends several months each year in Japan and abroad teaching in order to spread the teachings of Hokushin Ittō-ryū Hyōhō worldwide.