Midori Fuse is Nagisawa Shoma's partner. She is a cat type who is known to have cat ears under her witch hat which she is ashamed to show to others besides Nagisawa. This is due to her animal factors from the Gastrea virus which can strongly affect the body of the host. Nagisawa seems to have established a very strong trust to Midori.
Her corrosion rate later becomes too high as a result from being attacked by a Gastrea, and she later ends her own life because she believed she would only burden the team.