He promised he would come back for her. And he did. / The first time they met, the first time a man returned for her, the first time they came to Camp Half Blood, the first time she thought he was a complete fool (and the times after that). The many firsts in the relationship of Calypso, goddess of Ogygia and Leo Valdez, son of Hephaestus. (Post- HoH; CALEO)

SPOILER HOH: The crew defeated Gaea. As they sail, with Leo stands at the helm with the rest below, asleep, Festus reports that the astrolabe is pointing them north. It is suppose to point to Calypso, the only girl who has ever loved him. If he doesn't go, he might lose his only chance of finding her. Part of the prophecy hasn't been completed: An oath to keep with a final breath.