Amniotic Glow records three photo sessions, one in 2014 and two in 2019, between photographer Chikashi Kasai and model Manami Usamaru, two people driven by an instinctive desire for the photograph. Kasai, who has photographed many women, called Usamaru a rare subject with a charm that cannot be described in mediocre words, and chose to remain calm before her. In her flexible, unconscious eros and the gentle eyes that cherish what passes away, the book holds an important place in Kasai's history, and is also Usamaru's first all-nude photobook, a monumental work for her.