Predesincestion:
Marty didn’t know who was his father. His mom, Lorraine, only was saying “a stranger man that I prefer to forget.” so, thanks to his intelligence, he somehow built a time-machine to find who his dad was. He succeeded his project and time journey, too. He had traveled back in time to a time when his parents must have just met.
But things didn’t go as he expected and something terrible had happened. He fall in love his young mother and he named himself Calvin to introduce her.
A few days later, after a drinking party, he couldn’t help himself and they had sex, a quickie fuck. After that, he was completely devastated and he returned to his time with his time-machine without say goodbye to Lourrine, his young mother.
Poor Lourrine never forgot him or forgive him..
She couldn’t forget him because only a month later she find she was pregnant… and after she birthed her son, she named him “Marty.”
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