(This story is a little bit older, but I still hope you'll enjoy this. ^^)
Oroku Saki, also known as the one and only Shredder, sighed in satisfaction as the hot water of the tub touched his exposed skin, slowly sinking down until he was sitting. His legs were outstretched, and he leaned back, arms laid on the sides, until his back touched the end, relaxing all the muscles he possessed. Those dark irises were hidden behind those heavy eyelids which the man had already closed, and he let his head fall backward, fully relaxing into the warm water that was surrounding him.
His breathing was calm and even, his muscular chest rose and fell every time he sucked air in through his nose and released it through his mouth, letting his mind go blank. He let go, and dove into the water, letting the liquid swap over his face, flooding his black hair and beard, before he came to the surface again, getting into the same position he was in before. He felt how the water trickled down his neck, running over his chest before it melted with the rest. A rare smile appeared on his lips and the tension disappeared from his face, giving his relaxed state away. The soft light in the room did much for the calming atmosphere surrounding the man.
Minutes passed and the water swapped calmly against his now heated skin when he suddenly felt something soft caress his chest. Surprised, Saki's eyes shot open and he stared at the thing that dared to touch him, only to find a pink tentacle, softly rubbing his skin. The dangerous man chuckled and padded it with one hand before relaxing back again, letting it do whatever it wanted. Three more came and started to massage his shoulders and stomach and soon, four pink, strong limbs were gently rubbing against the sun-kissed skin, curling into a spiral, collecting water before letting it fall on top of his head again, and again.
He groaned slightly at the wonderful sensation as one of the tentacles massaged a tense spot on his right shoulder that he dislocated a while ago during a fight, slightly pressing into it. Suddenly, they grabbed the tubes and began to clean him, rubbing the soap into his skin. They took care not to hurt him in any means, even going as far as the rub the space between his toes. One cleaned his neck and stomach while another one made its way to his hair, pouring shampoo in and brushing through it, taking care of every knot that had formed itself in there and cleaning it in the progress.
He didn't bother about the slime, no, not at all. He had found out that it made it softer, so he didn't mind. Suddenly, he the third tentacle on a very special area, how the tip slowly ran up and down on a very particular limb of his body. He tensed, releasing a soft moan that was building up in his throat, raising his hip a little bit to give the limb better access. His member started to harden, and he could feel how all the blood ran down there, filling it more and more with each stroke the tentacle made. Suddenly, the fourth one retracted, but soon reappeared and wrapping itself around his balls, so that not only the hardening flesh was stimulated, but also the heavy balls.
The man swallowed a moan and leaned in even further, just enjoying the sensations, and soon, a huge erection stood proud between his muscular legs, thick and long, veins showing on the surface, and it was throbbing. The movement didn't falter, no, they got even steadier, and soon, he was groaning every time the tentacle ran up, huffing the air out of his mouth, which was hanging open, not caring about dignity. There was no one who he could look weak to, and with that wonderful treatment, he didn't even know if he would have cared. The tentacle running through his hair was so relaxing, the one massaging his shoulder was soothing, the other rubbing his balls was wonderful, and the last one stroking his cock was pure bliss.
Suddenly, he was pulled down by his hair, and he took it as a clue to dive, which he did. Shredder took a deep breath before breaking through the surface. The movements on his cock suddenly fastened, causing a little air to escape his lungs for the moan he released. His hair was washed out properly, and as soon as the pink tentacle was finished, he could finally come up and release a moan that was building in his throat as the pace slowed again and the tip was caught tightly in it, rubbing roughly. He leaned back and relaxed as best as he could with all the pleasure running through his body. The two tentacles on his hair and stomach disappeared and suddenly reappeared on his hips and butt.
They rubbed gently on the skin for a short while before positioning the human at a better angle to rub between the butt cheeks, carefully caressing the area there. He groaned and thrust his hips up to the creature, hissing at the sensation. The naughty, pink limb didn't seem to be satisfied and rubbed the little butthole softly. Dark eyes widened as he looked down, staring at it, as it moved between his legs, shocked, yet, at the same time, turned on.
He thrust his hips in its direction, giving his permission. The tentacle took it and pressed against it, slowly entering the tightness. The black-haired man gasped in pain, gripping the sides of the tub so hard it almost broke. He cursed and threw his head back, his face twisted in an expression of pain. The tentacles around his cock, balls, and hips fastened again, trying to hold up the pleasure he was feeling. The one inside him began to move gently, caressing the muscles that it could reach.
After a whole minute, the pain subsided and was replaced by that wonderful feeling of being filled, and he started to hiss every time when it thrust. A sudden cry echoed through the large bathroom as it found a very special spot inside him, ramming against it again and again. His hands that were still on the sides of the bathtub tightened again, he howled, pressing his hips, and he felt the wonderful sensation of being close to climax. His grunts and hisses got louder, his body tensed, and suddenly, a loud, strangled cry echoed through the room.
Everything went white for a second, and cum shot from the tip of the throbbing cock and mixed into the water surrounding him. He gave a low moan as it finally ended, pressing himself against the tentacles in pleasure, before slumping down, completely exhausted. Carefully, the one in his butt slid out, causing him to groan in discomfort. The others started to massage him again, and he made a small noise in his throat. The man looked up, a grin forming on his face as his dark eyes spotted their owner, magenta irises stared back, one of those limbs covered in his cum mixed with water was slid between plump lips and the creature swallowed. Krang laid there, looking at him, giving a grin on his own.