An expert hacker, serving as the operator for the Guerrilla Resistance Group "Undertaker". She is a cheeky 14-year-old and speaks her mind.
In season 2, Inori asks her is she ever felt loneliness. Tsugumi replies that she play with dolls to get away from the feeling.
Tsugumi is created by Redjuice Graphics. In the New York Comic Con panel with the three producers of Guilty Crown, Oyama states that Ayase's tight body suit is derived from Neon Genesis Evangelion's suits, and since Tsugumi wears similar attire to Ayase, this is also her inspiration. She first appears in episode 2. Her Japanese voice actress is Ayana Taketatsu.