Incest: Mother's opening

Yumi lost her husband in an accident and raised her son Yasuo on her own. He remarried to Kazuma, who had proposed to him despite knowing he had a son, and Yasuo and Kazuma, together with him, went to the beach. However, Yasuo refuses to remarry, and as if to show that his mother is her own, he buries her face into Yumi's crotch sleeping on the sandy beach and slides her hands over her voluptuous body. And even so, Yasuo couldn't contain his feelings, and inserted his dick into his mother's mature pussy. On a quiet, rippling coast...