After their mother died, their father was deeply affected and struggled to feed his family with fishing. One day, Neritos failed to from his fishing trip, which lead Agapios to believe him dead, even making him a grave. Afterwards, Agapios' father sold him to slavery, and he entered the service of the magistrate of Chalkis in Euboea. In time, he rose to be the magistrate's most trusted servant.
During the Peloponnesian War, a criminal organization known as The Dagger was able to extert their influence over the island. Agapios' master tasked him to uncover the leader of the Dagger as well as the reach of their whole operation.
Taking his investigation to the city port, Agapios met the misthios Kassandra who was passing through. Kassandra offered her assistance, helping Agapios to recover records from the heavily Chalkis Warehouse. Offering Kassandra further work, Agapios and his master met her at the Slave Market, requesting her to help them uncover the identity of the Dagger's leader, and demolish the group.
Following Agapios' clues, Kassandra uncover the organization's leader as Neritos, Agapios' brother whom he believed dead. They faced him at the Temple of Achilles on Skyros, and after learning that Neritos was unwilling to change his ways, Kassandra killed him.
- Depending on choices made in The Kingfisher and the Robin, Agapios can be killed by his brother. If he survives, Agapios is released from his servitude and remains the magistrate's friend, in Euboea.
- The name is derived from the Greek word, and feminine name, ἀγάπη (agápē), meaning 'love, affection'.