Nidome no Jinsei wa Koukai Shimasen ~Koufuku End wa Fukushuu no Ato de~二度目の人生は後悔しません～幸福エンドは復讐の後で～; I Won't Regret My Second Life: A Happy Ending Comes After Revenge

The husband she loved, the only friend she trusted. But at the brink of death, Sereniel realized the truth: everything was a conspiracy woven with lies and betrayal. At that moment, love turned into hatred, and she vowed revenge. At the edge of despair, the one she reached out to was the duke feared as the “Emperor’s Dog”—Lexion Rosenbester—ruthless and merciless, known for crushing any who opposed imperial authority. The coldest and most dangerous man in the world. The conditions he set to aid her were only two: First, completely abandon that worthless man. And second—. Thus began the dangerous contract between the two. Yet, there is no hesitation. Sereniel’s second life had begun solely for revenge.