Got a first-year female college student! Yuka, who's studying in the medical field, is a charming beauty with a constant smile. We approached her with, "We'll pay you a fee—would you cooperate with research and development on bidet toilet seats?" Her reply? "If it's just showing my butt hole, then haha," immediately spreading her gorgeous anus wide open, kicking off the anal research right away. We measured everything: anal color, size, progress rate, positioning, and more. To replicate the gentle water flow of bidet nozzles, we advanced the study by stimulating her anus with the tongue. After finishing the anal research and moving on to vaginal testing, her nipples became highly sensitive. Seizing the moment, she started giving my cock a juicy blowjob, so as a thank-you, I rewarded her with a creampie, thrusting deep inside her bare.