Mary was just a simple lady. She got up, went to work, and paid her bills. But like most people, they lived from month to month. She had always wanted to go on a trip. When she bid on the ticket, she didn't just want to go to Las Vegas or somewhere close by, but somewhere special and exotic. She wanted to win the trip to the Caribbean, but she knew she probably wouldn't.

She did her usual things. She got a call one day saying she had won this once-in-a-lifetime trip and could bring a friend. She was single at the time, so she called her little sister, who was about to go on spring break. They planned their trip and packed for the nice weather that was expected. They got on the plane and couldn't sit still the whole time. The flight attendant inquired as to where they planned to stay. They told her about Mary winning the trip while she sat with them after everyone else had fallen asleep. They admitted that they didn't know where they were going.

Mary fell asleep, leaving her sister Jennifer to talk to the flight attendant, whose eyes kept wandering to Mary's skirt, which had ridden up enough to show a little bit of thigh. Jen followed her glance. She smiled at the attendant and asked if she liked what she saw. Jen looked around to make sure no one could see her and then got up and followed her to the front of the plane. When she reached the front, the attendant closed the curtain, pushed Jen against the wall, and kissed her. Jen asked if looking at her sister's thighs aroused her.

She said, "Yes."

The plane shook once, then again. The captain turned on the sign that said, "Fasten seatbelts." Jen stumbled back to her seat and looked out the window at the lightning. Mary remarked that it was just her luck.

When the plane landed, they gathered their belongings before walking to the shuttle that would take them to their hotel. The clerk was very kind and polite. He welcomed them to the hotel and offered them a bungalow as an upgrade due to the weather. The warm air and rain made the room humid when they got there. The girls put on their bikinis, and Jen started to tell her sister about how she kissed the flight attendant to kill time. The girls, bored and annoyed by the weather, decided to go for a walk on the beach in the rain. The rain was soaking them as they walked and talked, enjoying each other's company until lightning struck a nearby tree, causing it to crash and block their path back. They were forced to walk through the jungle to get back to the resort.

When they returned, they took turns showering and getting ready for dinner. They learned about an after-hours pool party while eating in the dining hall. Excited to find something to do, they finished their dinner, changed into swimsuits, and made their way to the pool. They noticed about ten people standing in the rain. They joined them and discussed how they were all enjoying tropical drinks in the rain and jumping in the pool. The girls were talking to the receptionist when they saw the first top come off. Mary was shocked and turned to the receptionist.

"Is that okay?" She responded quickly. Nobody cared that it was an adult resort. Jen and Mary exchanged smiles. Both were still talking to the girl, noticing her dark blue bra beneath her soaked white shirt. When she realized this, she smiled and simply took off her top. She asked if the view was better. Jennifer grinned, reached over, and unhooked her bra.

"Now it is," she said.

Mary was shocked to see her little sister be so forward, but she wouldn't turn away. She saw a woman without clothes jumping into the pool. She realized that almost everyone was already naked. She stood up and removed her suit, hoping that her sister would feel embarrassed and leave. Jen, surprised, looked at her. She asked for her name before unzipping her skirt.

"Laura," she replied, letting her skirt and panties fall to the ground. Jen removed her own bikini and sat next to her sister.

"Are you trying to convince me to join a threesome?" Laura leaned in and asked. "Because I am in."

Laura leaned in and kissed them both, reaching out to cup their breasts. Their tongues danced together. Laura pushed Mary back onto the lounge chair, instructing Jen to straddle her face. She tried to protest, but Laura told her to do whatever she was told. She slapped her face. Jen was caught off guard. Mary was smiling and oddly aroused to see her sister smacked when Laura grabbed her blouse and tied Mary's arms above her head to the lounge chair. She pressed Jen against her face.

"Be a good little slut, lick your sister."

Neither of them had any idea what to do. They did what they were told. They noticed a crowd forming around them as Mary began licking Jennifer. Laura asked the audience if someone had a belt and used it to slap Mary's C-cups. Her nipples were already stiff from the rain, and the belt caused small marks on her tits. Laura spread Mary's legs. She leaned in and began licking Jennifer before whipping her on the tits and ass cheeks with the belt.

The people around them began to fuck as Laura instructed her sister. The simple pool party quickly turned into an all-women's orgy in the rain. Jennifer untied Mary after she had an orgasm. But before Laura could say anything, Mary picked up her panties and stuffed them into her mouth. She said it was her turn to be a good slut. Mary and Jennifer tied Laura to the lounge chair and told the other women to have their way with her because she was a good little slut who needed to cum repeatedly.

Mary looked at Jennifer and said, "I've always wanted to taste you."

As Jennifer looked at Mary, a glaze formed on her face.

"It took you long enough," she stuttered, pushing back and diving between Mary's legs. She began licking her sister with lust. Years of pent-up passion were released while Mary lay helpless under her sister's care. Rain showered them while they were having sex. The group around them reached out and caressed them as they expressed their passion and desire.

After the pool, they returned to their room and took a shower. Neither of them spoke. They tried but couldn't find the words. They got into bed and fell asleep. The next morning, still unable to find the right words, Mary looked at her sister sleeping next to her and pushed her hand into her panties. Jennifer woke up quickly. Mary just kissed her and kept fingering her. She felt her sister's pussy melt in her, and her hand leaked all the while. They kissed her deeply and wildly until she came.

The girls put on their clothes and went to eat. They saw that it was still raining outside. Jennifer's hand moved between Mary's legs as they sat down to breakfast. She pulled her bottoms to the side and tried to stay calm while being fingered under the table. She just closed her eyes and fucked her sister's hand. As Mary came, Laura walked up to them with a smile. She asked if they were having a good time on their trip. They just giggled.

The entire trip, it rained outside. It gave them an excuse to lock themselves up and fuck the entire trip. When they got home, Mary told her coworkers about how it rained the entire trip and how she would never forget it.