Main characters? Let's start with the obvious: Ludovica is at the center of everything. She's the duchess who wakes up with memories of her past life as a modern reader of the very romance novel she's now trapped in. That meta-layer is the whole hook. She knows the original plot ends with her character's tragic death, so her entire drive is to 'change the genre' from tragic melodrama to survival. Then you have the male lead, Duke Cladis. In the original story, he's the cold, tyrant husband who causes her demise. But through Ludovica's actions, their dynamic completely shifts—she's not playing the lovesick wife anymore, which throws him off balance and begins to alter his character fundamentally. Their interactions are a chess game where she's trying to rewrite their fate.
Supporting roles are key too. There's Serena, the novel's intended heroine and 'Saintess,' who Ludovica views with a mix of wariness and pity because she knows Serena's own destined path. And you can't forget Percival, Cladis's loyal knight, who often serves as a more rational observer to the strange changes in his liege's household. The real tension comes from how Ludovica's knowledge makes her react to these 'characters' not as people, but as plot functions she needs to debug, which slowly blurs as real relationships form. The magic system, tied to divine blessings, becomes another 'character' she has to manipulate.