Mother and son have sex in 2 seconds after father goes out

As if stolen from her husband's eyes, her mother Mai and her son Tatsuya had a relationship between a man and a woman. It's my fault that my husband doesn't care about his work. Mai was trying to make excuses to herself to escape her guilt. However, each day, her guilt towards her husband increases, and Mai, who can no longer bear it, tries to cut off her relationship with her son... Her son, who has become obsessed with Mai's body and has become a sex addict, can't stop. Even though Mai refuses in words, her body is hoping for her son...