"Please… I just need a mouthful." For fourteen years, Gayoon had lived like a little sister to Taejun, until the day she blurted out something unthinkable. "Give me just a mouthful, then I’ll quit. I’ll let it go." Gayoon has secretly loved Taejun all through the fourteen years they’ve lived together. One day, she accidentally catches him pleasuring himself. From that moment on, all she can think about is Taejun’s “thing”… and in the end, she can’t help but beg him for just a mouthful.