Aizen is one of the five Myō-ō (Sanskrit: Vidyarajas), 'Kings of Light', personified spells and protectors of the esoteric Shingon sect of Japanese Buddhism, whose principal deity, Dainichi Nyōrai (Mahavairacana), is the Buddha from whom boundless light emanates. Aizen is usually portrayed wearing a lion-skin hat or wearing a shishi head-dress and he sits on a lotus throne. He has six arms, each holding one of his attributes: bow, arrow, vajras (thunderbolts), some missing from this figure.
The figure is made of lacquered and pigmented wood, with crystal inlaid eyes and some metal fittings. The crystal eyes inset from the back of the head, the hollowed base and the treatment of the flesh suggest that it was made by a later artist of the thirteenth-century Kei school of sculpture centred around Unkei, the natural son of the sculptor Kōkei who revived the energetic style of the Tempyō era (AD 729-49). The pigment was probably reapplied in the nineteenth century when the dais was also restored.