[Kanzume] Tobikkiri Junjou Sister [Colored Heroine]

A devoted salaryman drags himself home past midnight to his cheerful younger sister Natsuki, who greets him at the door with dinner plans and a suspiciously wifely devotion — until she pins him down and reveals she's been using his sleeping body for her own pleasure all along. What follows is a frenzied power struggle between her squirting, ahegao-faced dominance and his degrading counterattacks, the two trading insults and bodily fluids while she begs him to put a baby in her and make an honest woman of her. By the final page her twintails are gone, her belly hangs heavy with his child, and the siblings have settled into something genuinely, disturbingly domestic.