Please Help Me Find the Manhua/Manwha: A demon woman is betrayed and killed by her farmer lover and his pink-haired saintess, who convinced him absorbs her power to become Emperor.

She reincarnates into his wife, an empress who killed herself and plots revenge on her former lover, the Emperor. The demon woman is black hair with red eyes as a demon and blonde as an Empress after reincarnation. The ML is brown skinned unofficial knight/consort and younger brother of a foreign king. The Emperor is blonde with purple eyes. The 2nd ML is a suave, white haired Duke and mage from the North. Due to a reincarnation contract she agreed to set by her demon sisters, if she falls in love with anyone he'll die.

The FL outmaneuvers the scheming pink-haired saintess during a diplomatic banquet, allies with the foreign queen, creates her own imperial military force, and recruits her former demon subordinate, a purple-haired bespectacled secretary. Later, she boards a luxury ship undercover to choose her own male mistress since the Emperor has one, where the ML immediately recognizes her and she meets the second male.