The serious overachieving younger sister 'Nana'. While studying in her room, her brother came in to give her a massage, but his hands became increasingly perverted and started groping her breasts... She has zero experience with men. Plus, the easily coerced 'Nana' ended up having sex with her brother! She might be good at studying, but she's clueless about H stuff. Despite feeling nervous, she ended up learning everything that feels good from her brother!
