Mona walked deeper into the cave. Behind her she could still hear the waves, crashing on the shore, and there was still plenty of light. The air was warm, and a bit musty. She thought she could hear the sloshing of water ahead, maybe another beach to explore? She carried on.
Mona rounded a corner and indeed, the cave opened up to another beach, the cave mouth ahead looking out toward open ocean and blue sky. White sands and stalagmites stretched into the crystal water. She happily stripped off her clothes and waded in to the sea. The water felt lovely and cool and the sand was soft under her feet. She waded forward and plunged her head under the water, paddling around a little in bliss.
Suddenly something grabbed her wrist and yanked. She looked down, putting her feet down in the sand and pulling against what looked a lot like an octopus tentacle. It extended down into the water, growing larger with every inch as it disappeared into the deep. She tugged out of the tentacle's grasp and turned back towards shore, half sobbing as she tried to get out of the water. Something wrapped around her ankle, though, and held her firm. Her other ankle also became ensnared, and as she flailed towards shore she felt something wrap around both wrists.
Mona screamed as her body was lifted into the air. Looking down below her she saw the sea writhing with massive tentacles, with two of them now tethered around her ankles and several large ones wrapped around her body, effectively tying her arms to her sides. She rose out of the water and hovered there, arms and ankles bound. Tentacles stretched up from the water and began caressing her body all over with soft touches, moving up her body the tentacles found her breasts and wrapped around them, the whippy little tips of them flicking her nipples. One tentacled slid up her body and wrapped around her throat, then slid up her face and into her mouth. It slid towards the back of her throat, feeling slick like it was secreting something. She was momentarily terrified it was going to slide all the way down her throat, but it stopped in the back of her mouth and began rubbing against her tongue. It tasted slightly sweet and slick, and she felt her head begin to spin. At the same time a sense of euphoria overtook her and she relaxed, zoning in on how good her nipples felt being rhythmically flicked by the tentacles.
A section of tentacle the size of a mans thigh slid up her back and she was gently leaned back against it, her body going limp as she lay back on the supportive arm. Her arms still bound to her sides, her ankles were pulled up and out, forcing her legs to spread wide as her pussy and ass were exposed. A tentacle began rubbing against her pussy, the extremely dexterous and apparently self lubricating tip began rummaging through her folds until it found her clit. It began massaging the little button with all the precision she would have used herself and soon she began to feel warmth spreading through her nether regions. A tentacle the size of a mans arm rose and prodded at the entrance to her pussy, pushing a few inches in as the first one continued to work her clit. It had a bulbus tip and felt remarkably like an enormous cock. She moaned as the tentacle pushed further into her pussy, growing even larger as it entered her. It wiggled as it slid inside, and Mona let out a moan around the tentacle that was still rubbing itself against her tongue. The massive tentacle began to slide in and out of her pussy, fucking her as it held her spread eagle in the air.
Mona felt another tentacle push against her asshole, but she was too blissed out to care. The thin, whippy little tip pushed easily past her sphincter as it entered her anus, and it wriggled as it fed itself slowly into her. She gasped and, as it continued to writhe in her asshole, she came, her body bowing back against the limb supporting her, one tentacle in each orifice sliding in and out as she was fucked by the sea monster.
