In the previous work, Kokoro-chan experienced her first encounter with an older man and underwent intense training with a large cock, leaving her unable to forget the overwhelming stimulation. In this installment, that experience deepens as she engages in sex at a hotel while wearing a special uniform, clearly showing how much she enjoys the situation. Her obsession with big cocks remains unchanged, and her transformation into a more aggressive lover becomes fully understandable when viewed alongside the scene of 'lessons=sex' performed in front of a piano.