Horizon AU Angela (Patreon)

Angela's story begins when she decides to leave her Nora tribe to explore and study the ruins. The desire to know more drives her to break the rule of the tribe - to never leave the tribe lands - therefore she becomes banished, never to return home. She spends years living in Cauldrons and ancient ruins, among the machines, studying them. She studies ancient libraries that survived and learns to build machines on her own. Not as advance as the originals but enough to modify human body and even use it as a weapon. She also takes a lot of ancient knowledge to heal people. 

One day she finds a man, that was attacked by a machine so badly that there was little hope for him. She decides to try and combine her healing and engineer knowledge to safe him. This is how she saves Genji Shimada.