Incestuous relationship with a huge penis: The mother, stuck to her son's hard, slippery cock, is captured. (Otsuki Hibiki NKKD-355)

"A beautiful and talented stepmother who, even after marriage, still wears a suit and works diligently to work, wanting to maintain a connection with society." Hibiki remarried to a man who runs a company. Even though her son is an adult, she still gently cares for him as a mother, though it's out of obligation, because she worries he stays home all day. But one day, after returning home from work, Hibiki is sexually assaulted by her son and pinned down. "No, Masaki-kun, please calm down!" As he licks her stockinged crotch, which is damp and hot from her workday, she gradually feels…!