My girlfriend's quiet and reserved sister, Yuhi, is so erotic... It all started when I was tutoring her, sneaking a quick touch. She suddenly started devouring my dick, and I was like, "Wait, she's right there!" Even though I was overwhelmed with a sense of guilt, I ejaculated with pleasure! Then, while she was sleeping, I gave her a footjob, carefully licking and sucking her ears and balls, and even licking her asshole, which she'd never even touched before... I felt so sorry for her... but I was so turned on that I almost forgot about it. Even after ejaculating, her inexhaustible sexual appetite like a succubus kept me pounding! She was gushing with love juices, making lewd, sloppy noises as I pounded her in the cowgirl position and came inside her! I thought she was a sweet and innocent girl, but she turned out to be a psychotic sex killer in sheep's clothing, craving thrills and pleasure... Before I knew it, I was captivated by Yuhi.