3 years ago, during the Mitochondria Eve revolution in New York, Aya, then an NYPD officer, joined forces with the Navy and contributed to the resolution of the incident. But at that same time, she was faced with the dilemma of the mitochondria within her own body awakening. After the incident in New York, Aya resigned from the police force out of consideration for her colleagues. She was quickly recruited for the undercover MIST organization and moved to LA to chase the NMCs (Neo-Mitochondrion Creastures), which were spreading to the West. Due to the awakened mitochondria in her cells, Aya appears younger than her actual biological age.