The story about how I came to be like this with my mother

A mother confesses to her son that she is having an affair with the mother next door.
He is asked to have sex with the mother instead of ending the affair.
At first, the mother refuses, but her son uses clever tricks to get her to have sex with him.
Eventually, she takes him into her body.

The mother is disturbed by the fact that her son is having sex with her as he pleases.
She learns that her neighbor's wife is also having incest and goes to her for advice.
"I have to hide it from the world, but it fills me up..."
The mother is determined to face her son and continue the physical relationship with him. She allows the relationship to continue.

One day, when the physical relationship with her son had become routine, she learned that the parents next door had moved out.
She was shocked to learn that the parents next door had divorced after their incestuous relationship was exposed.
This led to an awakening of the mother and son to having sex outdoors, but..,

When the son finally gets a girlfriend, they decide to take a mother-son hot spring trip to end the mother-son incestuous relationship.