Koga studied at Taiheiyogakai Kenkyujo, Nihon Suisaiga Kenkyujo, and other institutes. Based at Nikakai, in 1922, he formed an avant-garde group named Action together with young artists aiming at a new trend. While absorbing various trends in modern Western art, he left an original mark on avant-garde art in Japan from the late Taisho period to the early Showa period.
There is a reclining figure, but it is not a realistic portrayal. The body form is simplified and the individual parts such as the head, arms, and legs are combined in an awkward way as if they were each viewed from different angles. There are geometric forms and grids in the background and the upper part of the picture. The way the subject is analyzed from various angles and depicted by combining such analyses is typified in Cubism, a style which Picasso and other painters experimented with. On the other hand, there is also a somewhat visionary atmosphere in this painting. This is a sign of the influence the artist was under in those days from a trend known as Surrealism, which placed more emphasis on a person’s inner imagination such as dream, spirit, and unconsciousness than the real world visible to the eyes.