My Fiance and Junior Sister Stole My Incense Recipe; I Ruined Them

My fiancé and my junior disciple sister were carrying on behind my back, and they'd already decided my family's seven-generation Soothing Incense recipe was as good as theirs. To my face they played the parts of devotion and sweetness, while behind my back they stole raw ingredients, swapped out exhibit pieces, and even worked out exactly how to throw me out on the street once we were legally married. Standing before the hidden compartment in the study, I held the voice recorder and listened to every last one of their filthy schemes, a mocking smile curving my lips.