This is my entry for the Nicery Summer Contest

Percy did not expect to spend his seventeenth birthday in agony. Or curled up behind a rock near the shore, feeling scales shredding through his skin. And especially not with Nico hugging him from behind and trying to soothe him with kisses.

The day started out normal enough. He had woken up early, feeling exceptionally happy. He couldn't remember why exactly, but got dressed and headed over to the overly crowded dining pavilion to get breakfast. It looked like it was going to be a beautiful summer day. As he tried to avoid being trampled by the mass of kids, he snagged a sandwich from one of the tables and made for the beach.

As he sat down on a log near the water, he heard someone coming up behind him.

"Good Morning Perce" said a silky smooth voice, belonging to Nico.

"Morning" He returned. That voice always made his heart flutter.

Percy had always liked the boy, but those feelings became something more after the titan war. After they went through that, the Italian had a different aura around him. He was more mature, and seemed a lot more powerfull. And the fact that he had a growth spurt and became extremely attractive didn't hurt either. Percy had fallen hard for him. His fair share of wet dreams about Nico dominating him were proof of that. He was quite sure that his feelings were not returned however. They boy had always distanced himself from everyone, Percy even more so wasn't even sure Nico was into guys for that matter. And then there was the fact that Percy was to scared to actually tell Nico that he loved him.

He turned to look at the Italian. He was surprised to see him hold a muffin with a blue candle on top.

"What's that for?", asked Percy.

"Don't tell me that you've forgotten your own birthday again", Nico said with a grin.

Percy realized that today was the 18th. "In my defence, I was busy saving Olympus last time", he remarked.

"Happy Birthday mio bello" said Nico with a chuckle, and handed over the muffin to the green eyed boy.

A blushing Percy accepted the muffin. He couldn't stand it when Nico spoke Italian to him. He never knew what any of it meant, but it sounded so hot from the Italians mouth.

An intense pain suddenly went through Percy's legs and he took a sharp breath. A second wave hit him as he let out a cry of pain, and he clutched Nico's shirt for support. Said boy was instantly kneeled in front of him.

"What's wrong Percy, what's happening?" Nico said worriedly, a hint of panic in his voice.

"M- my legs", Percy exclaimed before getting hit by another wave of pain.

"I'm getting you to the water", said Nico as he lifted Percy up bridal style.

Normally Percy would be extremely embarrassed about that, but he barely registerd it as he was being carried towords the water. As Nico lowerd him into the sea he expected the pain to stop. Instead it increased gradually. He let out another cry, and tears started welling up.

"Nico please do something, it hurts, it hurts so much", he said while looking up at Nico with pain flooded eyes.

Nico was in a state of panic. When Percy had started feeling pains he carried the boy to the water as fast as he could, but this only seemed to make the situation worse. The water was supposed to heal Percy, it was his natural element. He was near crying as he saw Percy in so much pain. Why was this happening today of all times. He had finally mustered up the courage to tell the green eyed boy his true feelings for him. That he had loved him for quite some time now. Instead he was holding the one he loved with tears streaking his cheeks.

He waded back to shore and sat down in the sand, hidden from sight by a big boulder. He held Percy close to him, placing him on his lap while trying to soothe him by rubbing his back and murmuring sweet Italian words to him. He wasn't really aware of the fact that they were touching so closely until Nico felt something along Percy's legs. As he looked down he let out a surprised yelp. There were scales appearing along Percy's legs. They seemed to be breaking through the skin. He felt a wave of symphaty for the sea prince. It looked extremely painfull. As he absentmindedly wondered why Percy was growing scales, the boy let out a bloodcurling scream. Nico made a decision.

He stopped it with a kiss.

Percy had never been in this much pain before. He was faintly aware of Nico holding him and rubbing his hand along his back, saying things to him. He kept getting hit by wave after wave of pain, and was gritting his teeth against the screams. As he got hit by the worst one yet, he let out an agonizing scream, but it was muffled when he felt soft lips of his. As the kiss was broken, he opened his eyes and looked up at Nico in surprise.

It was then he became aware of what was happening to him. He could feel the scales appearing along his limbs. He felt his legs fuse together in a sear of hot pain, and rip his jeans and undergarments apart. He felt fins expanding, and sharp pains around his neck area told him that he had gotten gills. The last thing he heard as he blacked out was a whisperd "Così bello"

Nico could only stare as he watched percy being turned into the most beautifull creature he had ever seen. A sleek, elegant seagreen tail had replaced his long pale legs. He had fins sticking out of his arm, surrounded by scales and he could faintly make out gills along his neck. Percy's raven black hair only made him more alluring. There seemed to be some scales caught in his shirt, so he slipped it off the boy, revealing the faint outline of abs that came with a swimmer's body. He ran his hands over the sea prince's tail, marveling at its beauty while waiting for the boy to wake up.

Percy stirred. He felt something running over his leg, and sleepily tried to brush it away. He felt waves lapping at his feet, and felt safe in the others embrace. Wait. Embrace?

He panickedly opened his eyes and tried to scramble away from his captor, effectively face planting on the warm sand.

"Shh, mio bello, it's allright" he heard Nico's voice say as he felt arms being wrapped around him.

He turned around and looked at the other boy, who was looking over him worriedly.

"Why…, wh- what happened" Percy said, giving his tail a couple of nervous flicks.

It was only then that he realised he had a tail. A freaking tail. How would he be able to explain this to the others. He began to tear up as he ran all the possible scenarios through his head. He would be called a freak for gaining a tail. As far as he knew, no other demigod was able to do this. His biggest fear however, was that Nico would reject him. He wasn't even sure if he was able to change back. What if he was stuck like this forever. But he was convinced otherwise as he became aware of the other boy trailing kisses along his neck.

"So beautifull" said Nico who was staring down at him lovingly."

Percy blushed deeply at that, as he realized he was pretty much naked. Percy tried to cover up, earning himself a chuckle from Nico, who was staring at him with an affectionous look.

He suddenly got the urge to kiss that perfect face of his, and that was exactly what he did. The other boy leaned into the kiss, and deepend it, only breaking apart when they were out of breath.

"That was amazing" said Percy, while trying to catch his breath." I…I've been in love with you for a while now, but I never knew how to tell you"

"I think you've made your statement. I've been in love with you for quite some time as well" said a flusterd Nico.

Percy suddenly got the urge to return to the ocean. He was starting to get a burning sensation all over his skin, and was craving contact with the water.

"Nico, could you carry me to the water?" he asked.

"Of course mio bello" was his answer, as he was lifted up.

Percy felt rejuvenated as he was lowerd into the water, and immediately bolted off. It felt wonderfull to speed through the water like this, his tail giving powerfull flicks, and it truly felt like he was a part of the ocean. All he was missing was Nico. As he resurfaced a fair distance from the beach, he saw the boy worridly staring at the sea from one of the rocks sticking out of the sea, his eyes scanning the horizon. In a moment of pure happiness, he swam back and jumped out of the water to give Nico a peck on the lips. The look on his face was one he would never forget.

Later that day, they were sitting in a cave percy had found not long ago. Waist deep in water, Nico was holding Percy in his lap, who was enjoying the sensations Nico's fingers made when touching his sensitive tail. The Italian recalled what his father once told him about Poseidons children.

"According to dad, It's exceptionally rare. The strongest of your father's demigod children sometimes have the chance to have a special gene passed down, that enables them to take the form of a merperson. It usually happens on their 17th birthday. As far as I know you're the first one in about 500 years."

"But how long does it last then? Will I be able to turn back to normal?" asked Percy.

"Probably, but I wouldn't want you to, not for a while at least. You're so beautifull in this form. I want to ravish you while I can" Nico said with a wicked grin on his face, as he pulled Percy in for another kiss.

The boys faught for dominance, Nico eventually winning. Percy moaned against the other boys lips as Nico explored his mouth while he was raking his nails across his skin. As they broke apart, both breathing heavily, the sea prince felt something stirring in his nether regions. Nico had been rubbing against his groin all this time, and he became aware of he fact that something was slowly rising up.

"Nico", said Percy alarmed.

As he stopped leaving kisses all over percy's neck, he looked down. And saw a scaly member poking up.

"I don't remember dad telling me about this. But it means I should be able to make love to you while in this form", said Nico with a hungry look in his eyes, and his tounge darted out to wet his lips.

He slowly creeped his hand down to percy's now erect member. It was slick and scaly, but Nico payed no mind to it as he gently fondeld the tip, which started to leak a pearl-like pre-cum. The sea prince let out a wanton moan, at which he grabbed it and started pumping his hand up and down. His other hand went down to caress Percy's behind. He could feel the boy's scales starting to loose up and eventually retracting, revealing an inviting puckerd hole. An invitation that Nico gladly accepted.

Percy was a mess as Nico's hand pumped along his member. His new body was extremly sensitive, every touch sent a wave of pleasure through him. And then Nico inserted a finger. Percy arched his back and let out a cry at the intrusion. The burning sensation was odd as nico wiggled it around for a bit, added a second finger, and started scisoring them. Percy was holding back pained whimpers when he felt Nico hit a spot within him and everything dissolved into pleasure. Nico smirked and continued to stroke the sensetive bundle of felt something within him break, and he saw stars as he came, letting out a string of moans consisting of his lovers name.

As Percy came, Nico was captivated by the beautiful expression that was on his angelic face, flusterd red as jolts of pearly cum got splatterd over the green eyed boy's torso. As he finished, Nico got a sudden urge to taste his lover s release. He bowed down and licked some of it off of his stomach. The salty substance tasted divine, and he lapped the rest up as well. As he wiped his mouth, he was greeted by a shocked Percy.

"You taste wonderful, mio bello", said Nico in a husky voice, and went in for another kiss.

He could taste himself in Nico's mouth as the other boy sucked on his tounge. He was caught up in the kiss when he felt something poking at his hole.

"I'm sorry, but I can't wait any longer", said Nico, and with a swift motion he slammed himself into Percy.

At first, it was painfull. As Nico started moving, he let out pained whimpers. Nico whisperd words of encouragement in his ear and told him to relax. After a little while, the pain had slowly turned into pleasure. Lots of it. The other's cock was filling him to the brim, and it felt amazing. As he rocked his hips to meet with Nico, the other boy shifted and hit his prostate, electing more moans from Percy as he saw stars.

Nico grinned when he found that spot again, and focused on hitting it with each thrust. Percy was so thight, enceacing his cock in warmth. He grunted each time he slammed into said boy's ass, loving the feeling. The faces and noises percy were making were encouraging him to go even faster. He felt the pleasure building up within him.

"Percy. Come with me" coed the Italian, as he saw the boy was close to his release.

They were in pure estacy as they came together, shockwaves of pleasure rippling through them. Percy could feel himself being filled with Nico's release. As the shocks faded away, they pushed their foreheads together. Never had they been through something as intense as that.

"I love you", said both boys breathlessly to eachother, as they looked each other in the eye.

"This was the best birthday ever" whisperd Percy, as he lovingly pulled the Italian into a hug.

The End

So percy and annabeth were never together in this one, and the events of the heroes of Olympus books never happened. I just really wanted to have percy turn into a merman and Nico helping him through it. (Mio bello means my beauty, and cosí bello means so beautiful) Anyway, this is the first story I've written, so I'd appreciate it if you left me some feedback so I know if I should continue writing. Thanks for reading ^.^ (For anyone who noticed that the story is different now, i decided to add the smut part to the story x_x)