"Were you expecting that?" The voice of my childhood friend whispering in my ear is different from when he was a child, it's low and sweet. He thrusts his fingers into me and makes those embarrassing noises on purpose. I can't believe this cute guy has grown into such a man! Ritsu, a junior college student who aims to become a nursery teacher, comes to the house of her childhood friend, Yoshimi, who left her six years ago. In order to pass her piano exam, Ritsu takes lessons from Yoshimi, but... His breath on her ears and his body heat make her shake. "Ritsu, are you thinking of naughty things?"