The Holy Grail of Eris

In a court where nobles lie as easily as they breathe, Constance Grail stands out as basically the most upstanding person around — her entire family built their reputation on honesty and integrity. Which is great until her fiancé cheats on her and his new lover frames Constance for theft, leaving her socially destroyed with no way to fight back using just good manners. That's when she meets the ghost of Scarlett Castiel, a sharp-tongued noblewoman who was executed ten years ago for supposedly trying to poison a prince's mistress. Scarlett has her own agenda: she wants to know what really led to her death. So the two strike a deal — Scarlett helps Constance navigate the cutthroat world of noble politics, and Constance helps Scarlett uncover the conspiracy behind her execution. What follows is a mystery-driven story layered with supernatural elements, where two women with very different personalities dig through secrets that powerful people want buried. The dynamic between earnest Constance and the more cynical Scarlett is the real draw here — think odd-couple energy with actual stakes. The tone balances suspense with lighter moments, so it never feels relentlessly grim. If you liked the political intrigue and villainess angle of My Next Life as a Villainess but wanted something with more teeth, or if The Case Study of Vanitas scratched your itch for gothic mystery with strong character dynamics, this one's worth keeping on your radar for 2026.