Yoshiyama is an assistant of Koyanagi . She is nearly to become one of the death stench.
Assistant of Doctor Koyanagi, she cares for him and tries to help him. When she was seen with Tadashi by Kaori, Kaori tried to attack her. Ms. Yoshiyama then ran outside where she was captured by the Mechanical Koyanagi. Her final fate is never truly revealed; however, in the last moments of the series, her motionless body is seen connected to Doctor Koyanagi's flying machine.
- Well He's....(Yoshiyama guilty to tell the news about Koyanagi)