She was a female-warrior and a sorceress from Ireland who lived in Scotland with other Druidesses. Their task was to initiate and train young Celtic noblemen in the art of love and war. Queen Aife loved her chariot and horses more than anything else. She met with Cuchulainn and did battle with him.
Cuchulainn won the fight by cunning and forced her to give three things in return:
•That she became Scathach's vassal
•That she agreed to become Cuchulainn's lover
•That she gave him a son, Conlaech
Cuchulainn asked her to teach the secrets of war to their son and after the initialization to send him to Ireland. She trained Conlaech, but when he arrived in Ireland and met his father, Cuchulainn did not recognize him. They fought together and the result was that Cuchulainn was killed by his own son.
Source: yesss.perso.neuf.fr/Celts/Women/women