Clytemnestra’s lover and accomplice, and Agamemnon’s cousin. Aegisthus and Agamemnon’s fathers were brothers. Agamemnon’s father Atreus killed several of Aegisthus’ brothers and fed them to their father Thyestes. After Clytemnestra murders Agamemnon, Aegisthus justifies his involvement by saying that the murder of Agamemnon also avenges Atreus’s crime against Aegisthus’s family.