A lady of the "Yayoi House" during the time of the Dark War. She participated in the battle against the Black Beast, fulfilled her mission with the power of the Sealed Weapon Izayoi, and used up all of her strength in front of Hakumen. 
Ayame participated in a battle to stall the Black Beast. This battle took place because Nine needed more time to create the Nox Nyctores in Ishana. The estimated completion for the weapons was around half a year, but the Black Beast was on course to arrive in Ishana in four months.
Ayame first appeared when preparations for the battle were underway. She warmly introduced herself to Hakumen, who was the leader of the troops. The way she carried herself, her appearance, and her name caused a twinge of nostalgia to stir within Hakumen.
The first day of the battle was a nightmare. The Black Beast, a creature they thought to be mindless, used military tactics and lured them into an ambush. Many troops fell, and they had no choice but to attempt to retreat; however, the Black Beast made escape impossible. Amidst the chaos, Ayame approached Hakumen and requested to break through the frontlines; Hakumen inquires about the Sealed Weapon Izayoi and Ayame explains it was a weapon entrusted to the Yayoi household. The sight of the weapon causes Hakumen unease. Without waiting for a response from Hakumen, Ayame roused herself and activated the Izayoi to make a frontline assault; out of reflex he tries to stop her, but she was gone in a flash of light. This action created an opening for the troops to successfully retreat.
After retreating, they made camp later that night. Ayame lay dying in a tent due to her use of the Izayoi. She was visited by Hakumen, and she spoke to him despite struggling with every breath. In her last moments, Hakumen comforts Ayame by holding her hand, and her finals words were solemnly expressing she felt honored to fight alongside him.
- BlazBlue 10th Anniversary Site (JP), Ayame Yayoi
- BlazBlue: Phase Shift 4, Chapter 2: Sweeping Away Crimson Grief, Page 64
- BlazBlue: Phase Shift 4, Chapter 2: Sweeping Away Crimson Grief, Page 88-89
- BlazBlue: Phase Shift 4, Chapter 2: Sweeping Away Crimson Grief, Page 96-104
- BlazBlue: Phase Shift 4, Chapter 2: Sweeping Away Crimson Grief, Page 105-106
- BlazBlue: Phase Shift 4, Chapter 2: Sweeping Away Crimson Grief, Page 109-113