After actually watching this work, I was unexpectedly drawn into the story of Masao, an unremarkable virgin, being toyed with by his popular older brother's wild friends with benefits. Masao leads a plain life focused solely on studying, but he's intensely curious about sexual matters, and his innocent personality adds a unique tension to the entire piece. The development where, the morning after his brother leaves for work, the seductive Karen and devilish Yuki, fueled by leftover alcohol, close in on Masao is more thrilling than anticipated, gripping the viewer's heart. Karen's mature allure and Yuki's youthful energy blend perfectly, with Masao's confusion and excitement portrayed so realistically that it feels like you're right there in the scene. Especially, Masao's transition from bewilderment to surrendering to pleasure in his first experience captures a slice of youth, offering many heartwarming moments. This work goes beyond mere entertainment, delving deep into human instincts and growth, with new discoveries on every rewatch. I highly recommend it to everyone.