Spoilers for

Red Ranger Becomes an Adventurer in Another World - 1st chapter takes place during Episode 3 of the anime. The rest of the story takes place after Chapter 28 of the manga

Kaizoku Sentai Gokaiger - Takes place after Gokaiger Ten

Chapter 1: Keys Unlocking Bonds

After a long, and honestly absurd to even explain, day of retrieving Mana Metal, Yihdra Arvoln was in her laboratory analyzing her newly acquired materials thanks to her new companion Asagaki Togo, also known as Kizuna Red. Remembering how he would yell out that name before being followed by an unexplained explosion (said explosion that ruined her flooring and almost killed her), Yidhra wondered if this metal was worth putting up with Red's reality-defying antics.

"His powers are certainly extraordinary and could definitely be my starting steps to working towards reclaiming the Royal Scepter, but that guy could be the death of me!" she thought. "But, he said that he would protect my dream. Maybe I should go looking for him tomorrow."

As she was going to retrieve more crystals from her supply, a bright red flash from the pile caught her eye. "What the- is something reacting to the Mana Metal?" Yidhra exclaims. She digs through the pile to find the flashing shard. Inside the shard was seemingly a glowing red figurine. As Yidhra went to pick it up, the glowing stopped and she could see the figurine more clearly. It was primarily red-colored, immediately reminding her of you know who. But looking more closely, the design of it was different from the red-colored, spandex-wearing, loudmouthed adventurer she knew.

The mask had a symbol resembling a black bird with a gold outline and the chest had these black straps, also with gold outlines. The straps on the chest had a line with a divot in the middle, seemingly making the letter M. Originally Yihdra thought that this was just some toy that somehow got encased in the crystal. "With how these crystals were formed, this toy should be broken and shown its wear and tear. But, it's in near pristine condition!" Going to satisfy her curiosity, Yihdra when and analyzed this toy, and what she found made her damn near collapse on the floor. "The amount of magic energy in this thing is absurd! Apparently, this thing has an affinity for fire? How can a toy have an affinity for fire!?"

Calming herself down, Yihdra goes through some hypotheses. "Maybe it's like an enhancer for fire spells?" Seemingly the most logical explanation, she heads down to her front lawn and sets up some rock pillars as testing dummies. After testing casts of fire with and without the red trinket, Yihdra concluded that the figurine had no difference in her magic power. "Sigh, well that was a bust. Well, this might just be another reason to find him tomorrow morning." With that, she decided to put the study on hold until she could retrieve her test subject fellow adventurer.

The Next Day

After getting into an argument and then working a job with two idiots, including a very close encounter with a powerful unknown treasure monster, followed by more of Red's insane power showcase with a 'power of bonds' speech (as well as maybe starting to appreciate his company), which was then followed by another embarrassing moment at the adventurer's hall, topping it all off with the building exploding thanks to Red transforming and her having to cover the damages. Yihdra was ready to call it a night, despite it being in the middle of the day. "No! Come on body and brain! He's right here and staying at my house! This is the perfect opportunity!" she thought with a grin. Going to the guest room that Red was staying in, she knocked on his door.

"Hey, Red! You in there?" She called.

"Yeah!" Red replied. A few seconds later, the door opened to show the familiar red-haired Red Ranger. "Did you need something, Yihdra?"

"Yeah, I was just hoping that we could get some more tes-"

SPLATURN!

She was interrupted by Red's bracelet and him doing a transformation pose.

"NONONONO! WE ARE NOT DOING THIS A THIRD TIME, ESPECIALLY NOT IN MY HOUSE! I PROMISE TO KEEP AWAY FROM THE NEEDLES IF YOU JUST DON'T TRANSFORM IN MY HOUSE," she shouted

Assessing her body for any presence of needles (while trying to avoid a few exposed areas), "You promise?" he said with a serious but somewhat fearful face. "I promise," she replied with a hand on her heart. Red finally loosens up and stops his transformation sequence.

"Ok, what did you want to test with me?" Red asked as he closed the door.

"Actually, it was more to ask you if you knew what this was," Yihdra replied as she held up the red trinket from yesterday. "I found this encased in the Mana Metal that we retrieved on our first adventure. At first, I thought that it was one of your toys that you were talking about when we first met. But, I analyzed it and it has a massive amount of magic energy and an affinity for fire. I tested it to see if it was an enhancing item, but nothing about my fire changed. Since this thing looked a lot like your suit, I wanted to ask if you knew."

Red proceeds to pick up the trinket and examine it closely. "It does look like some type of red ranger, but it's definitely not me or my toys. The design of the suit itself is not something I recognize either. But, did you try pushing this button?"

"What button?!"

"This button on the side." Red pointed out. He proceeded to press it, and then the legs and the arms of the ranger lifted upwards while making a small little 'click' sound. The back of the legs revealed a symbol that was unfamiliar to the two, and what was behind the legs was revealed to be something resembling the teeth of a key.

"Is this a key?" Yihdra questioned.

"Maybe? If this does unlock something, you should probably keep this on you then," Red said while putting the key back in its original position and handing her back the key. "Sorry that I couldn't help you with anything," he said while doing the cliche scratching behind his head pose.

"No, I probably never would have figured out that this was a key without you. Maybe this key can unlock a greater power or something, or at least lead to good loot," she replied with an endearing smile.

CRACK!

The door bursts open revealing Poseidon as the one who kicked the door open, Yihdra's Butler/Surrogate Grandfather, holding a pair of scissors with grim intent.

"Sir Red, I mustn't allow you to take another step closer to My Lady before I castrate you."

A struggle breaks out between Red and Poseidon as both Red and Yihdra plead for him to stop, but those requests were ignored with Poseidon repeating that this is for her own good. The struggle then ends when the three notice two strangers have entered the building, appearing to be a Noblewoman and her Knight. Unfortunately, the struggle ended with Red laying on top of Yihdra while both were directly in front of the two strangers.

"Going at it like rabbits even at noon, Huh?" said the Noblewoman

"Lady Teltina… Please refrain from making such remarks as a lady." said the Knight

CHAPTER 1 END

Author's Notes

I want to say thank you for reading my first story. I fell in love with Tokusatsu and Fanfiction for a while and finally had the passion to write my own story. Gokaiger is my first and favorite season, and I fell in love with Red Isekai the moment I read the first chapter. After getting caught up with the manga, immediately thought of combining my two favorite Tokusatsu related series, especially after the anime. This is being written before Gozyuger airs and I have not seen every Sentai season and movie so some Sentai lore may be inaccurate to the official series. I hope you enjoy as I continue this story.