Revenge For The King Of The Household: When I Gave My Sister, Who Was Always Superior To Me, A Sex Drive Enhancer Concentrated 100 Times As Revenge, She Fell Into A Frenzy And Got A Boner Even Though She Was My Little Brother. Rei Kamiki

I hate my older sister. After our father was laid off, her income became the sole lifeline supporting our household. From that moment, she transformed into the absolute king of the family, treating everyone as her personal servants with constant condescending looks and superior attitude. Seeking revenge mixed with a half-joking impulse, I took a dangerous libido enhancer entrusted by a friend, concentrated it a full 100 times, and secretly administered it to her. The extreme effects hit hard: she plunged into a drug-induced frenzy, her judgment shattered as she fell into a weak, completely broken state. Even though I am her younger brother, the sight and situation left me fully aroused. What begins as calculated payback spirals into an intense, addictive cycle of dominance reversal, endless nights of escalating desire, and a sister who can no longer stop despite knowing the truth.