Sex-Dad
(noun) A ‘man about the house’ who is a non-blood relative and enjoys cohabitation and sordid romps with one’s natural mother. In modern parlance - your mom’s live-in boyfriend or lover.
Teacher: Scooter, will I be seeing your mom and pop at the Parents Evening tonight?
Scooter: Mom’ll be there – she’s bringing my Sex-Dad.
Scooter: Mom’ll be there – she’s bringing my Sex-Dad.