One day, my sister's ass drove me wild. I secretly created a mysterious liquid in my room that multiplies mucous membrane sensitivity by tens. I sneak into her bedroom while she's asleep and inject the liquid into her anus. Unknowingly, my sister's anal sensitivity increases, and she becomes addicted to the anal pleasure. Emboldened, I prepare an IV drip and inject a massive amount into her rectum. My sister's sense of self collapses from the immense quantity injected into her anus, and she goes wild with anal sex.
