Becoming the Brother of the Gong

<Former Obsessive Madman Gong (Younger Brother) x Iron Wall Adult Su (Older Brother)> I became the protagonist's older brother. But that protagonist... He's the obsessive madman gong from a 19+ kidnapping, confinement, and angst-filled story... I have to educate him. *** 20 years later, I finally thought I'd made him into a decent human being, but... "The aroma that hyung likes. I just sprayed it." A sharp and heavy scent that oppresses the whole body and turns the head into mush. This isn't an aroma. It's a dominant alpha pheromone. "You must be tired from meetings all day. I'll give you a massage when we get home." A touch that strokes from the cheek to the chest, from the chest to ...