My mean sister usually makes fun of me, her little brother, and relieves her stress. To vent my frustrations, I sprayed her with a rumored hypnotic spray in the city, half-jokingly saying, "I'll turn into a perverted woman," and she suddenly dropped her head and started fingering me without any hesitation. She then started drooling and sucking my dick, sitting on my face and doing handjobs. I didn't know what to do, but I got an unexpected erection, so I let my sister do what she wanted.