Human and Merman: love story

Charlotte was a young woman in her early 20's. She had normal life in the city of Miami, on day at her work her closest friends surprised her with a luxury cruise for 2 weeks for her birthday that's coming up in 5 days! Her birthday has finally came and her friends and everyone aboard celebrated her special day. The day was paradise, perfect! At least, it WAS. She was asleep and notice the violent shaking, while her friends stayed asleep. She ran outside seeing huge waves crashing against the ship. She attempted to tell her friends to wake up and get out, but that section of the ship was flooded with water. She was too late... She ran back outside and right after she opened the door, she was washed away with the wave and into the water. She later woke up finding herself in a underwater cave with drawings all over the walls. She looked in the water finding... a merman?