Reika was always sweet to her son (Takahiro), and Takahiro was also sweet to such Reika. One day, Reika sees Takahiro masturbating in Reika's underwear. Reika behaves as if she doesn't care about the upset Takahiro. Takahiro asks Reika for fear. "Mother will make me a man?" Reika responded to Takahiro's thoughts with her hands ... and with her mouth, though she was confused. However, on the contrary, Reika is not enough with that alone, "Troublesome virgin baby, mother will teach you to the end" Reika teaches Takahiro to gently wrap cunnilingus, fingering, missionary posture, back ...