"This is awesome!" Derrick cried as he swam in the beautiful ocean, his majestic royal blue tail gleaming in the sea.
"It is isn't it little brother!" Julie said
"Indeed it is" Miley said, "However, there is something I need from you, in particular you Derrick"
"What is it?" Derrick asked curiously
"You see," Miley said, as she floated in front of Derrick "There is a low population of mermen compared to mermaids in this area, and today is mating season..." As she did this, she slowly stroked Derrick's tail.
Derrick let out a loud moan as Miley continued to stroke his tail, Julie stared at Miley unable to believe what she was hearing, but that was when she felt a weird sensation in her body, as if someone had lit a fire inside of her. Her hand indirectly went over an area on her tail as she began to rub it.
"And younger mermen have high fertility" Miley said as she began to remove her top "So...I am going to need you..."
Julie gasped as she saw something come out of Derrick's tail. 2 large penises came out of a sheath, as Derrick let out a large loud and long moan. "To mate with me"
Thoughts began to clash in Julie's mind 'I need that cock!' 'he's your brother!' 'I need that cock to fill me up!' 'this is incest!' 'I want that cock to impregnate me!' 'HE'S YOUR BROTHER!'. Julie was in heat. She can't help it. Her mind had gone haywire! She felt extremely horny and she needed a cock in her now!
Miley turned to look at Julie, her face with a wide smile "Do you want me to go first? or you? There's a cock for one of us"