I Hid The Crazy Grand Duke’s Time-limited Younger Brother

I found myself transmigrated into a novel full of obsession and tragedy, but I didn’t care one bit. I was neither the heroine nor the villainess; I was just a passing noblewoman. I felt a bit of remorse for the heroine, who would rescue a child and suffer at the hands of the villain, but the male lead would save her in the end, anyway. I had nothing to worry about in my life. “This is insane! Are you crazy, Brother?!” Until my lunatic older brother came to me and said, “I have a gift for you!” and brought THAT child! “Doesn’t he resemble that stray cat you used to like when you were little?” Whatever! Take him back right now! * * * ‘It’s fine, as long as I don’t get caught…’ I pretended to help the villain, who was madly looking for his missing younger brother, while I secretly kept an eye on him. I was determined not to hand the child over to a human who wanted to use his little brother as a pawn in war, but… “Rayna, tell me.” His grip on my ankle grew stronger. “Why do you keep lying to me and hiding Calyx, my little brother?”