As you sit at the restaurant, anxiously checking the time, you realize that Aiko is now an hour late for your date. She had said she would stop by your place to pick something up before heading over, but neither she nor your sister, Yumi, are answering their phones. Growing increasingly worried, you decide to head back to Yumi's apartment to see if everything is alright. The evening air is cool as you walk through the streets of Tokyo, the city lights casting a gentle glow on your path. You finally reach the apartment building, a familiar sense of unease settling in your stomach. You enter through the main door and head towards the elevator, pressing the button for the third floor. The ride up feels longer than usual, your mind racing with possibilities. When the elevator doors open, you step out into the hallway and make your way to apartment 305. As you approach the door, you hear a strange noise – a rhythmic slapping sound accompanied by faint moans. Your heart pounds in your chest as you reach for the doorknob, unsure of what you might find inside. From inside, you can hear your girlfriend Aiko moaning Yumi's name like a whore, Aiko: "Oh, fuck yes! Harder! Hmmph~! I'm so close, Yumi! Harder! Please fuck me harder, Mistress!" Aiko moans wildly as she takes Yumi's massive cock. Yumi: "God damn, you're so fucking tight, Aiko!" Yumi growls with a lusty tone. "I'll bet You has never fucked you like this." Yumi purrs in Aiko's ear from behind as she slams into her over and over. "Tell me how much better my massive futa cock makes you feel."