Jealousy

On the way home, Thea grumbles despite focusing on the pavement before her. His mouth wouldn't stop ranting about how stupid and clumsy marc had already revealed his true identity to Pauline.

Though it's seen a few times that it wasn't a big mistake, there's still a little suspicion surrounding her about Pauline. That made Thea feel that Marc's honesty, as well as the spontaneous nodding she gave him in the cafe earlier, was a mistake.

Marc didn't make a mistake; Thea did. And the resentment was growing.

Marc doesn't deny ranting and resentments Thea spills on him. Marc let the girl go on a rampage. Marc regained consciousness; he and Thea made a mistake together. They're not up to the deal.

Marc should hide his identity from anyone, while Thea should pretend not to know and not claim that she is a traitor who has called Marc, breaking Marc's curse.