The Condemned Pharmacist's Daughter Fights Evil with Poison

https://www.cmoa.jp/title/299262/

Countess Angelica was striving to restore her family's fortunes in order to repay her deceased parents. One day, while steadily building up her achievements as the director of the Royal Herbal Research Institute, tragedy struck—she was framed for a crime she didn't commit by a young lady who was supposed to be her fiancé's best friend, and made to look like the perpetrator of illegal drug manufacturing! Far from restoring her family's fortunes, she had brought shame upon them, and as Angelica grappled with her helplessness in prison, a certain man visited her—"I can't let the real culprit get away. How about we make a deal, Angelica?" The charismatic, villainous young lady, with the pride of her family in her heart, will punish her traitors with poison!