Rick's a horny teenager and his Grandpa is a horny old man. When Grandpa arrives at Rick's house with a mind control formula, Rick's world changes for the better.
After Dad is killed, son takes charge as timid mom surrenders control. He eventually coats her vaginal walls with incestuous sperm and makes her his woman.
When I was a teenager, 17 years old, my family had a ski boat, which we used on many summer weekends and evenings. We lived close enough to the lake that we would often go water skiing for a couple of hours when Dad got home from work in the evening. It was during one of these short, evening ski trips that the experience I'm about to tell you about happened.
A son finally loses control of himself, and finds in his mother a more than willing partner. She inducts him into manhood, and begins teaching him how to properly please her.
A mother makes a rash promise to her daughter on her 18th birthday that she will go along with anything the daughter wants to do to celebrate. She chose sex - with her mum!