First fanfic of this type, the idea came to me while watching Moana. First chapter will be a bit boring/weird due to exposition but will get to the sinful smut. Will be adding other girls in later chapters. Please tell me what you think/suggestions.

Warning: This contains smut, lemon, futa, incest (Elsa and Anna), and other content. It will mainly be light and smutty, nothing super serious. If you do not like it, do not read it.

*Disclaimer: Frozen, Moana, Brave, Mulan, and all other Disney movies are owned by the Walt Disney Corporation. I own nothing!*

Firstborn

Ch. 1 Girl from the South

It was a long traditional ceremony where all the nations sent delegations to Arendelle to reaffirm their treaties with the new Queen. Why they couldn't have done this a year ago at her coronation when the dignitaries were all already here, Elsa wasn't quite sure, but she did know that this was mandated by law and not something that could be ignored. While the parade of nations started excitingly with each delegation wearing their traditional ceremonial clothing, Elsa soon became tired and beleaguered as each delegation stated that they were Aredndelle's most important ally and then droned on and on about random parts of the treaties, and normally tried to fit in the fact that they had a bachelor prince. Well, all the delegations but Dunbroch whose Princess Merida was just as unorthodox as Elsa coupled with the fact the entire delegation was already drunk and they lost their copy of the treaty. Her sister Anna, however seemed to be enthralled the entire time with the spectacle from other nations. Her holding Elsa's hand through the entire thing was really the only thing that got Elsa through the long afternoon. No one except for the two of them knew their secret and their special promise.

The last delegation did capture Elsa's attention. They were from a group of Southern Islands that no one had been to or heard of and shocked everyone when they sailed into Arendelle's port earlier that morning in their primitive looking boats. The historians quickly scoured their books and discovered that over a century before, the rulers of Arendelle had signed a treaty with the Island People who eventually vanished and no one had heard from them in a thousand years. The archivists were quickly dispatched and showed up covered in dust moments before the Island People's turn with an ancient scroll and a hastily written memo detailing the major points of the treaty. Then everyone realized they could not speak their language until it was discovered that the wizard Merlin from the Camelot delegation somehow knew their language and was quickly recruited as a translator.

The men were impressive wearing grass skirts, ceremonial headdresses decorated with flowers and feathers, necklaces and anklets made of stones and shells, and covered in intricate tattoos. Even though it was colder than they were used to and they were shirtless, they did not look effected by the chill. However, it was the girl about eighteen years old that Elsa couldn't stop looking at. She was introduced as the Chieftain's Daughter and was the leader of the group, she was also the one that steered the lead boat into port. She was tall and muscular with long curly brown hair, beautiful brown skin, and curves in all the right places. She wore a red top that covered her medium sized breasts and a white skirt that exposed just enough of her midriff, an anklet of shells, a necklace made from precious stones, and a flower crown. She was one of the most beautiful women that Elsa had ever laid her eyes on. She smiled and bowed for Elsa at the beginning but preferred to let one of the men do most of the talking. Halfway through, Elsa realized she was probably being obvious staring at the girl so she started looking around the room. It turned out that Princess Merida and Commander Fa Mulan from China also looked very interested in the girl.

The ceremony finally drew to a close, and everyone exited the room to head to the great hall for the banquet. Elsa flicked her long blond braid over her shoulder and smoothed out her blue dress before turning to Anna.

"Anna, I'm so exhausted. Can we skip the dinner?"

The beautiful red head smiled at her before saying, "And start an international incident? I don't think that would be wise for a new Queen. I'll tell you what. I'll head into the banquet and distract everyone and you go back to our room for a few minutes of alone time and then head back when you are recharged."

Anna always knew that Elsa needed her alone time, and Elsa loved her for that. She kissed Anna on the cheek, "Thanks Anna, you're the best." And quickly escaped back to their shared room using a secret passageway. When she arrived back in their room, she flopped herself on their large bed and closed her eyes. Suddenly, she heard a noise. She looked up and saw the Island girl coming through the secret passageway.

"What are you doing here!?" yelled Elsa surprised before realizing the girl wouldn't understand her.

The girl shocked Elsa by speaking. "I've come to see you." She said.

"You speak the common tongue? Why didn't you tell anyone?"

"Yes, I can speak your language. Us Wayfinders have our mysterious ways. I needed to know if Arendelle could still be trusted." And she smiled, gazing at Elsa.

"Uh, ok. What is your name again and why do you want to see me?"

"I am Moana. I've heard legends of the Ice Queen in the North, and I needed to meet you. I know your secret."

"Well of course you know my secret, everyone knows about the ice magic. Not exactly a secret."

"No, your other secret." Moana said this time looking down Elsa's blue dress at her waist.

"How? How do you know about that? Only my sister and some trolls know." Elsa was shocked and surprised. She thought she could keep this part hidden from the rest of the world leaders.

"You are the firstborn daughter of Royal Blood. I am the firstborn daughter of Royal Blood. The gods gave us special gifts to ensure we continue our family lines. Surely you know this." Mona said as she walked towards Elsa.

"I, I don't. I never asked anyone about it."

Moana smiled as she stepped closer, "I'll show you mine if you show me yours." And with that she lifted her white skirt to show both her vagina covered in brown pubic hair and a large penis and two heavy testicles.

Elsa starred for a long time before being able to speak. "I didn't know anyone else was like me." She then lifted her dress to show her shaven pussy and an equally large penis with heavy testicles.

"Well, it does look like we are a match then," Moana said smiling before reaching to grasp Elsa's dick which started to harden.

"Match? Wait no! I'm already um committed to someone else. I made her a promise."

"Her?" Moana smiled again, "I can deal work with a her. Did you not read our treaty?"

Elsa quickly tried to remember the memo. It mostly talked about deep sea fishing rights and something about the importation of coconuts. "Do you want to fish in our waters?" she asked confused.

"Well yes, but we'll talk about that later. No, did you read the last part of the treaty? The part written in the Royal language? The part that your advisors can't read?" Moana said while handing a copy of the treaty to Elsa.

Elsa flipped to the end and saw a paragraph written in a different language. She then realized she could read this language.

"What is this?"

"It is the Royal language that can only be read by those with Royal Blood. Have you Northerners forgotten everything about your Royal ancestors?"

Elsa ignored her and started reading "If both families has a firstborn daughter of marrying age, then they are to be wed to unite the two families. Then they must each give birth to at least one child to continue their Royal Blood lines."

She read it again. "Wait, we have to get married? Why is that in the treaty?"

"I don't know. You are the one that agreed to the treaty five minutes ago."

At first Elsa was angry for being tricked, and then she realized that she was the one that agreed to a treaty without actually reading it. She should have learned that lesson after Anna accidentally bought a crumbling castle.

"Is there…" Elsa started before Moana cut her off as she started stroking Elsa's cock.

"No, it is blessed by the gods and believe me, you do not want to experience the wrath of the gods."

"Ok, so we get married. Wait, what are you doing?"

"Well, after we agree to marry we must then draw out each other's seed to seal the deal. Then we can have the wedding. A bit backwards, I know." Moana said before kneeling and putting her lips around Elsa's cock. Elsa was taken aback by Moana's forwardness but then started to enjoy it as she started stroking Moana's curly hair. She had only ever had sex with Anna, and loved having Anna suck her penis. She never imagined being with anyone else. As her member became harder, her pussy became wet as well. As if sensing it, Moana inserted a finger into Elsa's pussy and began messaging her clit with her thumb.

This was almost too much and Elsa gripped Moana's hair. "Moana," she yelled, "I'm about to cum." Quickly, Moana stopped sucking and grabbed a cup off a bedside table and pointed the tip of Elsa's penis into it and began to rapidly jerk Elsa off. Elsa soon felt the double orgasm from both genitals crashing down on her, her seed spitting out into the cup while the juices from her pussy flowed down Moana's hand.

Elsa flopped back onto the bed. "Gods! That was exciting! How did you learn how to do that?"

"Well," Moana said licking her hand and then licking the left over cum from the tip of Elsa's penis. "I used to hang out with a very horny demi-god and have spent a lot of time on boats with very horny men. I've picked up a few things here and there. Ok, my turn. Make sure you aim me into the cup."

She stood up and undid her skirt to show that her cock was already completely rock hard dripping pre-cum and laid it on the bed. Elsa then climbed off and got on her knees. She had never done this before, or really had seen any other penis besides her own. She began stroking it and hesitantly kissed the tip before licking the precum. She then took it completely into her mouth and began sucking on it just like Anna does and Moana did. Her other hand fondled Moana's balls, before reaching down and inserting a finger into Moana's wet pussy. This part she was familiar with both with Anna and playing with herself. Moana moaned. "Well you are good at this," as she closed her eyes and stroked Elsa's long blond braid. "Whoever you've been sleeping with has taught you well."

Elsa began to speed up as Moana moaned louder, "Get the cup!" she yelled, "I'm cumming!"

Elsa quickly grabbed the cup and jerked Moana off until she came into the cup as well. Her juices leaked down onto Elsa's hand. Elsa began to lick it off as well, but then Moana leaned down and licked Elsa's hand. "I've always thought I taste good." She said winking at Elsa. Elsa almost came again.

Elsa looked down at the cup. "Um, what do we do with this?"

Moana looked at it as well before picking up the treaty. "Well, according to this, we both drink from it in order to seal the match." She took the cup from Elsa's hand, "Well, bottoms up!" she said as she took a drink of the seed before handing it to Elsa. "Well it does taste good."

Elsa hesitated before drinking. Moana was right, it did taste surprisingly good, slightly salty.

"So, are there any other weird rituals we must partake in?"

"Not right now. Are you ready to be my future wife?" Moana asked pulling Elsa up to kiss her. They kissed for a long time before breaking away.

"Yes, I am. Are you ready to be my future wife?" Elsa said as she placed her hands around Moana's perfectly curvy bare hips and stared deeply into her eyes.

Suddenly they heard a noise and spun around to see Anna standing at the door.

"Uh Elsa," Anna said stuttering, "What the hell is going on?"