Tsukasa, the sister who is played with as an oral sex slave by her real younger brother. She is subjected to intense throat-fucking that seems like it will pierce through her throat and cheeks, lewdly drooling saliva, which her twisted brother slurps up making 'slurp slurp' noises, and further, when he spreads open her vagina and performs cunnilingus, she exposes a sloppy face of ecstasy as she reaches orgasm. Even though she knows it's wrong, she climaxes over and over again from her younger brother's relentless torment.
