"Tatsuya Yoshida, born in Kitakami, Iwate is a Japanese musician; drummer and composer who is the only consistent member of the renowned progressive rock duo Ruins, as well as Koenji Hyakkei. He is also a member of the progressive rock trios Korekyojinn and Daimonji. Outside his own groups, Yoshida is renowned for his tenure as drummer in the indie progressive group YBO2, a band also featuring guitarist KK Null, whom he also joins in the current line up of Zeni Geva and he has played drums in a late edition of Samla Mammas Manna. He has been cited as "[the] indisputable master drummer of the Japanese underground". Along with his participation in bands, he has also released several solo recordings."

Keiko Komori: "I play the clarinet and saxophone in Tokyo. Member of KOENJI HYAKKEI and more."

Kengo Sakamoto is a Japanese bassist and vocalist recognized for his precision, stamina, and adaptability across progressive rock, jazz fusion, and avant-garde settings. His style blends driving rhythmic solidity with melodic inventiveness, supporting complex ensemble arrangements while contributing vocal harmonies and occasional compositional input.

Kei Koganemaru is a guitarist and vocalist whose work spans progressive rock, experimental music, and fusion genres. Known for his crisp articulation and dynamic range, he moves fluidly between intricate riff-driven passages, atmospheric textures, and expressive solos, often pairing his playing with strong supporting or lead vocals.

Taku Yabuki is a keyboardist and composer active in jazz fusion, progressive rock, and contemporary instrumental music. Equally adept at acoustic piano and modern synthesizers, his playing combines harmonic sophistication with rhythmic drive, and he has contributed arrangements, improvisations, and vocal work to a variety of studio and live projects.

AH is a vocalist distinguished by a commanding range and theatrical delivery, drawing on influences from classical, rock, and experimental traditions. Skilled in both lyrical singing and non-verbal vocalization, AH brings an expressive, sometimes operatic intensity to performances, adapting to settings from intimate chamber music to high-energy avant-rock ensembles.