My girlfriend's mom is a mom who does mommy work - real-life version Himari MIMK-231

The protagonist visits his fiancée's home and meets her mother. This mother had supported him through charity work during his student days, and they had shared sexual experiences multiple times. Unable to forget these experiences with his mother, the protagonist begins to seek her body. Sometimes beside his daughter, sometimes in the hallway late at night… Because they haven't had sex in a long time, the mother cannot resist the young man's forceful advances, repeatedly engaging in physical intimacy while unable to have sex with her daughter.