[Super cute subjective & binaural recording] I have a cheeky little sister, Ichika. She always tries to get the upper hand in both her studies and her love life... "If you do well on the mock exams, I'll do anything you want for three days, you idiot bro! Whatever?" It's time to get back at this brat! I worked as hard as I could, and finally made my little sister my personal maid! Her underdeveloped body...