Joren was faced with a difficult question. The answer is easy to find but to answer it is difficult.
Fortunately for him though, this Goddess is not of Anger but of Jealousy. But that plus side doesn't pull up the whole situation.
"I lied to you, I'm not Gyges, I'm just a lesser undead."
Joren came out of it. This is because Megaera already knew that he's lying, she wasn't just sure to who. However, she's not being hostile to him. This gave him a chance to say the truth.
"No, you may not be Gyges but you shouldn't be a lesser undead, stop lying!" Megaera said, her patience turning zero.
"But… I'm not lying. That's actually the truth."
Joren wanted to say that the soul Megaera gave to Allecto was his. But him being aware of that would question his intentions in courting Allecto.