@DRp not 100% same but this manga remind me novel 'akuyaku reijo ni koi', same about villainous lady fall in love with her butler, multiple reincarnator, but more heavy and dark story (war, manipulation, scheming etc)
I understand if the slave is from war or criminal, but that slave is deceived by slave trader and sold them?! I hope mc send assassin for that slave trader after this
Human mood affected by hormon, so reiji make medicine for reducing certain hormon not mind altering, and please we only want to have fun here not arguing about this