Born in 1739, he studied Neo-Confucianism under Yabu Kozan and Yamada Gessu. Originally known as Teikan, he took on the art-name (gô) of Kaimon. In 1783, he became an assistant teacher at the Kagoshima domain school Zôshikan, and after passing through official posts as Records Magistrate (Kiroku bugyô) and monogashira, he was named a full instructor at the Zôshikan, with a rank of sobayaku. He later became a Confucian instructor at the Shôheikô.
At one time, Akazaki was ordered by Shimazu Shigehide, lord of Kagoshima, to travel to Edo and to speak with scholars there, in order to bring knowledge back to Kagoshima. In Edo, he developed friendships with Rai Shunsui and his son Rai San'yô, as well as Shibano Ritsuzan and other notable scholars of the time.
In 1796, he interviewed Ryukyuan scholar-officials Tei Shôkan, Sai Hôkin, and other members of the 1796 Ryukyuan embassy to Edo, at the orders of Shimazu Shigehide, lord of Kagoshima. He then compiled what he learned from these interviews into a book titled Ryûkaku danki ("Conversations with Ryukyuan Guests"), which was published the following year.
Kaimon died on 1802/8/29.