Only a couple of characters can be romanced in Hades if Zagreus builds a strong relationship with them, including the former boss Megaera, First of the Furies. Forming a strong bond of love can be refreshing compared to the violent connections made with the many monsters you face every run. You’ll have to actively pursue different dialogue interactions with Megaera for any chance to deepen her bond with Zagreus.
Nearly every character and companion NPC in Hades can be talked to, whether during a run or within the House of Hades hub area. However, a very small portion of those characters have any romantic intentions toward the Prince of the Underworld. Megaera is perhaps the hardest character to romance due to her status as one of the first bosses you fight in every attempt to reach the surface.
Similar to romancing Thanatos in Hades, you need to gift Megaera bottles of Nectar to strengthen your bond with the First of the Furies. However, this can prove fairly difficult, as you tend to encounter Megaera on the field of battle during a run. You need to wait until Megaera appears in the House of Hades hub area between runs to properly gift her the delicious drink usually reserved for a god’s offering.
Usually, Megaera hangs out in the Lounge area of the House from time to time as you prepare for your next run. Don’t be too hasty to brave the Underworld, especially if you have Nectar on hand to give to the First of the Furies when you can interact with her. Once you have given Megaera around five bottles of Nectar, she will appear in Zagreus’ bedroom after a random number of Fury battles to trigger a unique interaction.
The dialogue between Zagreus and Megaera here reveals that Megaera never wanted to fight the Prince and that she only does so because it is her job. The next time you see the First of the Furies, you can gift Ambrosia to her to increase her Affinity Level for you even further. Try to give Ambrosia to Megaera every time you see her from this point onward to speed up the pace of one of Hades’ best relationships.
Eventually, after enough Ambrosia, Megaera will appear in Zagreus’ room again, causing a short cutscene to play where the two characters interact more intimately. At this point, you can choose to either enter a relationship with the former boss or choose to remain friends. Picking the option to openly be with Megaera will complete her romance in Hades, leading to unique interactions for the rest of the game, reflecting the new bond.