"Teacher, I'm an adult now, you know?" A teacher reunites with his former student, Sayaka, for the first time in 10 years. "Since we're here, I'd like to talk more..." she says, taking him to a love hotel. He is flustered when his ex-student seduces him, but when she whispers sweet words into his ear, he can no longer suppress his desire and becomes immersed in immoral sex. Who would have thought that such a diligent and Kokoro girl had such a lewd side hidden inside her... "I'll satisfy you with sex that feels better than your wife."