Her father Professor Gast was shot to death by troops led by Hojo, and she was taken into custody in the ShinRa Building with her mother, Ifalna.

She escaped from the ShinRa building with her mother, but Ifalna died at the Sector Seven train station. Elmyra took her in and raised Aerith as her adopted daughter.

She met Zack in the Sector 5 church, and became very intimate with him.

She was saved by a member of the Turks after she rejected a heavy-handed demand that she assist AVALANCHE.

While selling flowers in Sector 8, she met Cloud by chance just after the bombing of the Sector 1 Mako Reactor.

She met Cloud again when he fell through the roof of the Sector 5 slum church. She offered him one date on the condition that he act as her bodyguard, and then had him escort her home.

As Cloud and company went to stop the dropping of the Sector 7 plate she was entrusted with Marlene, but when they are captured by ShinRa she agreed to be taken to the ShinRa Building in exchange for Marlene's safety.

Cloud and company are thrown in jail while trying to rescue her, but then take the opportunity made by Sephiroth's murder of President ShinRa to escape out of the city. Cloud and company then decide to chase after Sephiroth.

She learned that Sephiroth planned to summon Meteor, and knowing that she had to stop this, she separated from the party to act on her own.

She sent her prayer for Holy to the Planet, and immediately afterwards lost her life at the hands of Sephiroth.

She used a portion of the Lifestream to stop Meteor's descent.

She appeared to Cloud from the spiritual world, trying to ease his painful sense of sin and guilt.

She joined everyone in the fight against Bahamut-SHIN, lent her power to the people suffering from Geostigma, and personally provided for Cloud's recovery.