Sawako Tokiji is the Chairwoman of F.L.A.G. and one of the heirs to the Tokiji Company. In the past, she was engaged to Karasawa Shiro, and it is heavily implied that she became pregnant with his child. When he was captured after turning into a Kanshu but could still control his mind, he talked her into releasing him by claiming he was in pain and then attacked her. The resulting injuries rendered her unable to bear children anymore, and she stated that the attack also killed the child she was pregnant with.
Sawako had a twin sister, Sayako, who was killed on Hatsumi Island and turned into Ende. However, Sawako was unable to become a Lost Rebound and completely forgot about Sayako until seeing Ende on F.L.A.G.'s Longest Day. Upon seeing her, she finally remembered Sayako and ran outside the base, and Ende brought her to her so they could talk. However, after Ende was defeated, Sawako disappeared and her current whereabouts have been stated to be unknown.(Source: World Embryo Wiki)