SEIKIMA-II was a heavy metal band with a style similar to that of US rock band KISS. Even though the band was very popular in Japan, outside of Japan they were rather unknown. The band's lead singer, Demon Kogure, was cited by many as having one of the best voices in the Japanese music scene. The other members contributed their voices to the choruses of nearly all their songs, adding to the vocal strength of the band. With their music, they contributed heavily to the evolution of Japanese heavy metal.
Visually, over time the band gradually abandoned their KISS styling soon after the final line-up had been established. From that point onward it seemed as if they got their inspiration from Kabuki theatre, and this fit quite well with their demonic image. Their make-up, which had been their trademark, remained the same.
Their fans affirmed their tendency towards black humor and satire—SEIKIMA-II fans were called 'Shinjas' and concerts were called 'Black Masses.' Additionally, they invented a new kind of time dating system. According to the band 1900 was the year 90 B.D. Further examples of their strange rewriting of time appear on their webpage, alongside other strange facts including Demon's weight declared as being somewhere between 58kg and 50000 tons.