Disclamer: I own nothing except this story.

(A/N): This version of Cortana in this story is going to be Halo 4, while Master Chief is going be the recent Halo 5: Guardians version, and Sergeant Johnson will be in his remastered version (Halo 2 Anniversary). I love Halo since it first came out. Halo 5 is awesome and can not wait for the sixth installment. And this is the very first Halo Little Mermaid crossover ever. Enjoy. Halo forever!.

Chapter 1 (Guardian)

Cortana was currently watching John-117 aka The Master Chief getting himself ready for their big mission. A mission that involve him to be a combination of being a guardian and security guard to a infant princess. Of course this was not their cup of tea since they were still in a war with the Covenant, and the UNSC is going to fight them without their number one sparten. Plus, Sergeant Johnson is going to join them on this mission to help assist John and beef up security for the palace.

Now, usually this request was rare and have to be given a great reason. For one is that the king and queen of Denmark did not have outstanding security and have an incident with their enemy, in which has a history behind it in which neither Cortana or Chief have no clue including Johnson himself. And also that the king and queen were their resource supplier for raw materials.

"Come on Chief, this is a good job for you. It won't hurt to take a break from fighting the Covenant." said Cortana trying to lighten up the sparten.

Master Chief grabbed his helmet and put it on his head. Then he pulled Cortana out and put her chip into the back of his helmet, and see her appear in his visor screen. He grabbed his signature assault rifle and place it on his back along with placing his pistal on his leg, and exit out of his room for the final time to go to the hanger.

"It's a permanent mission, Cortana." begin Chief, "Yesterday was our final fight in the war. Of all the Spartans we've have, why me?."

"Easy. The king and queen of Denmark wanted the best of the best spartan. And so they want the Master Chief himself." Cortana said, giving him an innocent smile.

Master Chief sighed when getting into the elevator after getting a few salutes from a few soldiers. "Still Cortana, I needed more on the battlefield and not babysitting a future spoiled girl princess." said Chief.

Cortana rolled her eyes. "Chief don't say that. This is an opportunity for you to be a normal soldier and be more social for once."

"Being less social is one of my best things about me." said Chief, smiling in his helmet on his joke.

"Like I said, this is good for you, me, and Johnson. And speaking of Johnson." Cortana said, when looking forward.

There sitting down on one of the shipped cargo smoking his fresh rolled cigar was Sergeant Johnson, who looked absoultyly ready for this permanent mission based upon his facial expression. He looked up to his best friend and pulled out his cigar from his mouth, and got off from the crate with his gun in the other hand before turning the safety on. Johnson can tell that his best friend/brother in arms was not too thrilled to go on this forever mission. "Chief you will feel a whole lot better if you just accept it. That is how I did it when getting the word from Admiral Hood."

"You're gonna miss putting a bullet through a Covenant soldier's head." pointed out Chief.

"Don't tempt me John." Johnson said, joining the walk with Chief.

"It's going to be worth the effort and honest work. Any soldier on Infinity would do down right anything to get this golden opportunity you know?." said Cortana, being cheerful and honest on the fact.

Chief folded his arms and said with sarcasm. "Oh, I feel so special Cortana."

"Academic wise or just plain old challenged?." said Cortana, trying Chief's intelligence.

"Whatever." camed Chief.

When reaching their assigned super upgraded pelican dropship and saying their last goodbyes to UNSC INFINITY, they took their seats with Johnson seating on the other side while Chief sat on the opposite. Besides the poilet who is flying the ship, it was only Chief, Johnson, and Cortana on board the pelican while taking the time to talk more on details of their new permanent home. After all their arrival to their mission is going to be hours from now.

"The Denmark that we're going to is Denmark-2 on the second planet of earth. Earth-2 to be exact." informed Cortana.

"Huh, so we're going to a planet that is two solar systems away from the Milky Way." said Chief, while leaning back in his seat.

"Earth-2 is completely tech free." begin Johnson while taking a few puffs from his cigar. "Which means that our people is in the Renaissance era of the freaking twentysix century. It's a damn shame too."

Chief lean his head to the side in shock and confusion. "Wait do they know what's actually happening in these years?."

"Yes, but the Covenant does not know of Earth-2's existence. Thus, making the planet safe and far away from the 'Endless War' of the human race against the Covenant." pointed out Cortana.

Johnson chuckled at Chief's expression even through his wearing his helmet and said after holding his cigar, "Don't worry Chief, I arranged us a tech spot. A small workout center, outdoor training facility, radio connection, and even tv. Well, of course the king and queen have a few tech in their home but, it's not the type of modern living."

"Great." Chief said, a bit unhappy. "How long to we reach Earth-2, Cortana?."

"About a good six hour flight, Chief. Even though we're in hyper speed. It will be nightfall when arriving to the castle." informed Cortana.

Six hours have went by until they entered the solar system where both Chief and Johnson looked to see Earth-2. The planet itself looked like a big beautiful blue marble thus, making its neighboring planets look absolutely gorgeous to look at. The ship begin to enter the planet's atmosphere with slow ease heading straight for the country of Denmark. Just exactly what Cortana have said, they were going to arrive doing nightfall. The pelican headed to the off coast of Denmark in which was where the royal castle is located with no problem. The first thing that they saw was the castle walls that stood high to the point you can not see anything, and noticed that the walls were freshly built based upon its looks.

"Those walls are specially made with strong titanium metal covered with normal wall material. Assuming that they don't want no one in." suggested Cortana.

"Or nor thing. Security is tight around here." commented Chief.

Johnson put his cigar out and said with honesty, "If that's true then we shouldn't be here now would we?."

Chief looked at Johnson with a nod. "Very true."

Once the poilet flew inside the border wall and landed on the landing zone, the Chief and Johnson were welcomed by the king and queen royal troops who stood side by side, and saluted them with high respect when two begin to move forward. They walked for a short minute until facing the king and queen of Denmark, who they were both pleased and relaxed from anxiety to see them on their doorstep. Master Chief looked at them to see that they were in their night clothes with bedroom slippers and all, and took the moment to observe their looks since this is his first time meeting them. He looked at the king who have fair skin tone with short black hair and light blue eyes, and looked like a pretty boy in Chief's opinion. Next, he looked at the queen who was very happy to see him here as she have the same skin tone as her husband, with the exception of her having red long hair but wrapped up in a royal hairstyle and having a beautiful jewel crown on her head. Chief can easily tell that the queen had experience of royalty by childbirth, but had the down to earth attitude in which that's rare based upon what Cortana has told him.

"Your Majesty's." Chief spoke formal with a nod.

"Master Chief. It is a real pleasure to have you, Sergeant Johnson, and your AI to be living here with us. My name King Eric, but you can just call me Eric." said Eric, showing his down to earth attitude.

"And my name is Ariel. I'm thankful for you three to stay here. Please, allow our men to unload your things into your rooms and follow us." said Ariel, when she and Eric entered inside.

Chief and Johnson followed the two, and looked amazed at how nice the inside was from the outside while finding themselves walking up the steps to somewhere that they do not know. Chief was shock and surprised to see that the steps were holding his combine weight of his armor and body fat, otherwise he might find himself making a big hole in the steps.

"We want you two to feel right at home." begin Ariel.

"And whatever makes you guys feel comfortable then don't be shy to ask." said Eric, with a smile on his face.

"If you guys have cuban cigars then please, don't mind if I do." said Johnson, before breaking a smile.

Eric looked back at him and smiled. "We have some for you in your room. Fresh off the boat."

"That sounds good." begin Johnson, who could taste the cigar.

"Anyway, what is our given assignment?." spoke Chief, who wanted to get his new job on the way.

Both Ariel and Eric stopped in the middle of the hallway and looked at the two with a normal look on their faces. They were informed on how the great Spartan-117 was more of a soldier than a relaxer compared with Sergeant Johnson but, that will change when he deals with his top assignment.

"Forgive him Ariel and Eric." said Cortana. "His antisocial and less take it easy kinda of guy."

"Don't worry that will all change in a few years." informed Ariel, giving a friendly grin.

"I seriously doubt that." said Chief, when folding his arms.

Eric begin clearing his throat before saying what he planned on saying. "Right well, for starters, Sergeant Johnson you be in charge of the troops. In which results in training and better up in our security defence, and basic security for the castle with everyone in it. Let alone the citizens of Denmark. Think you can handle it?."

At that moment the former spartan smirked big with that question and answered it simply. "Sir, I trained combat killing marine machines. This is nothing more then a cakewalk to me."

"Great. You can start first thing tomorrow morning. Your bedroom is just around the corner to our left. Night." said Ariel.

Johnson answered back by tipping his hat before heading to his new room while giving the Master Chief a hit on the arm. Chief did the same to him but gently not to brake his arm before removing Cortana out of his helmet, so she can appear in front of Ariel and Eric and gave them a friendly smile.

"Now where is that little bundle of joy?." Cortana asked cheerfully.

Ariel beamed at the AI and said nicely. "She is in her room sound asleep."

But then all of a sudden the four heard crying from the room in front of them and knew that it was none other then the baby. Truth be told that Ariel and Eric's daughter was getting restless after the whole incident at the sea from last week, and in which resulted the tight security wall, and special request soldiers from the UNSC. Ariel sighed with a sad smile while Eric had a rather tired look on his face as he and, his wife have to once again take turns on making their daughter to stop crying in the middle of the night.

"She has quite the set of lungs on her." commented Chief.

Cortana looked back at Chief. "Yeah, no kidding."

"We're sorry." Ariel begin still holding the sad smile. "Melody is recently restless at night and it take hours until sunlight for her to go back to sleep. She is quite a hand full as an infant."

When Eric open the door he let the Chief enter the room to see a bed designed for the young princess on when she gets older, before seeing the beautiful purple babycrib in which is where the source of crying was heading. Cortana leaped out of her chip and head over to the crib and looked at the princess. It did not take long for Chief to walk over to where Cortana stood at the edge of the crib looking down at the still crying Melody. That is until little Melody stopped her tears and cry when seeing the Master Chief staring down at her. Ariel and Eric were shocked to see this reaction since their daughter would cry more when seeing anyone in the castle to come see her, let alone trying to make the attempt to hold the little girl. At that very moment it made a beat into the Spartan's heart when seeing how downright adorable she is as, Cortana smiled big at seeing the princess was taking interest in her spartan.

"She likes you, Chief. Her temper and anxiety have went down to zero percent when looking at you." said Cortana.

"That was a big giveaway." spoke Chief.

At that moment the two quickly heard giggling from Melody as she had her arms out. Wanting to be hold by her new protector. Feeling the need to do what was asked if him he reach down and gently picked up Melody and hold her in his big arms. The little girl laughed happily before finding herself yawning and fallen asleep in his arms with a smile of happiness. Chief turned around to face Ariel and Eric who was happy to see that they picked the right spartan for the job.

"Your job Chief is to protect, guard, and care for Melody. Whatever you and Cortana do...please don't never let her go Chief." said Ariel.

"They are evil and dangerous people out there who wanted to harm Melody, Chief and Cortana. No matter where she go, you go as well even if she asked you not follow or order you to come." said Eric.

Chief looked back at the still sleeping Melody and noticed that the child is holding his left index finger without noticing it. For once in his life he was actually relaxed and cooled with his new job, and begin tolerating his permanent mission. Cortana jumped on the Chief's right shoulder and bend down to look at the innocent baby as it warmed her hologram heart. She wanted to make sure to strongly assist her spartan with everything she can do in order for Melody's safety to be intact.

"Sir, Ma'am." Chief looked back at Eric and Ariel with his chest out. "You can count on Spartan-117."

He looked back at Melody and smiled at the girl in his helmet. "Don't worry about a thing Melody. Your Guardian is here."