This is about Thor's twin sister and Loki's best friend, Dalla Odinsdottir. She is the Goddess of Fire, and has both passion and temper to match.
As with any Goddess story, it starts at the beginning of the first Thor movie with the children walking.
Difference in this chapter: Dalla is inserted into key scenes. We also catch hints of another character and some of Dalla's backstory.
Odin walked his children through the weapons vault, telling the tale of his victory over the Jotun. The three of them, the twins, Thor and Dalla, and their brother, Loki, hung onto every word in awe.
"But," Odin said, standing in front of the Casket of Ancient Winters at the end of the tale, "the day will come when one of you will have to defend that peace."
Dalla took her brothers' hands as Loki asked, "Do the Frost Giants still live?"
Dalla followed up with, "Will they attack us again?"
Thor removed his hand from hers and stated with a flurry of arm movements, "When I am king, I'll hunt the monsters down and slay them all! Just like you did, Father."
"A wise king," Odin counselled, looking at each child, "or queen, never seeks out war, but they must always be ready for it."
Odin began walking back. The three siblings looked at each other for a moment before running to catch up. The boys held Odin's hands while Dalla clutched Loki's free one.
"I am ready, Father," Thor proclaimed.
"So am I," Loki and Dalla said in unison.
"Only one of you can ascend to the throne," Odin replied. "The three of you were born to be kings or a queen."
Dalla snuck out to see Heimdall. She knew no one would notice she was gone apart from Frigga and Loki, who both knew what she planned. Though Loki wished to travel to Midgard with her, she didn't want to start an incident. She needed a break from lessons and endless training as a warrior and princess.
"You are well prepared, princess," Heimdall greeted.
"I shouldn't be long," she said, "unless there is a worthwhile war needing my attention."
"Enjoy this. The king won't allow another."
"I know. I plan to make the most of it."
With that, she travelled through the Bifrost. For several months, she stayed when, without warning, she returned.
"Call Loki," was all she said, tears threatening to fall.
When he arrived, he went to his sister, teleporting her to her room instantly. She changed out of her clothes into a nightgown and laid down.
"What happened?" Loki asked, his voice filled with concern as he sat on the bed next to her.
"I fell in love," she said as tears fell. "A soldier, a true warrior equal to any here on Asgard."
"Did you and he…?"
"No. He was very honorable." She sat up, hugging him tightly as she sobbed. "He sacrificed himself, Loki. He saved so many and he… he…" The curtains alighted. "It hurts. It hurts so much."
Odin, Frigga, and Thor stood in the doorway, having heard everything as they had walked through the hallway. Frigga ran to her daughter to soothe her.
"You should not have become so entangled with the mortals, daughter," said Odin. "If you had not…"
"Father, is this really what you want to do?" Loki asked. "She is grieving and you wish to lecture her?"
"She is emotional, brother, but the pain will pass," Thor said.
Dalla laid back down as she said, "I only want Mother and Loki to see me. I'm sure that won't interrupt any plans."
"Sister…" Thor began.
"Please!" she all but screamed.
Odin and Thor left. It was many weeks before she left her chambers. Loki visited her daily, becoming closer than before, almost inseparable. When she left her room, she was disillusioned by Odin and Thor. She no longer trusted them as she once had.
Odin was harsher with her after that, but like her raven-haired brother, she was biding her time.
She only trusted Loki with stories of her soldier. She regretted never telling him what had grown in her heart during their time on the battlefield. She told him as much as she could before the tears fell, but she couldn't fight the pain saying or thinking his name caused. Her soldier's name remained a mystery to her favorite brother.
Dalla stood between Loki and Thor. It was Thor's coronation day. She ignored their usual byplay. Princesses are to be quiet and keep their tempers in check. She repeated that mantra with a small smile, knowing her father wanted a proper girl to marry off. She and Sif were two of the best warriors and women long ago, yet he still tried to keep Dalla on a leash. The two of them proved Odin wrong on women not fighting, and now, Dalla carried the striking Eldr, a sword of flames.
Though her trusted weapon and deep red armor brought awe to some, the color caused all but her family to give her wary looks. It didn't help that her temper tantrums as a toddler lead to singed curtains or market stalls going up in flames. She no longer cared for the image the people saw, though it still hurt.
She and Loki entered the grand hall, standing close to Frigga. They watched Thor walk down the corridor of guards as the people of Asgard cheered him on.
"He postures like a peacock," she whispered to Loki. "Yet it looks like he tried to brush his hair with that hammer of his."
Loki snickered with her before adding, "No, but he did mess with it after he found worms in his breakfast this morning."
Dalla snorted, earning the two of them a glare from their mother. They composed themselves as Thor came nearer. Odin quieted the people by raising his staff and lowering it with a great boom. Thor knelt before his father.
"Thor Odinson," Odin began, "my heir, my first-born."
By five minutes, Dalla said telepathically to Loki, who fought to keep his face serious. Clearly, you got the brains and I got the looks, brother.
Many women say I'm dashing, Loki replied back.
Only because you are a prince, she retorted.
Odin, oblivious to his other children's conversation, continued, "So long entrusted with the mighty hammer, Mjollnir. Forged in the heart of a dying star. It's power has no equal! As a weapon to destroy, or as a tool to build. It is a fit companion for a king. I have defended Asgard, and the lives of the innocent across the Nine Realms, in the time of the Great Beginning. And though the day has come for a new King... Do you swear to guard the Nine Realms?"
Thor said, "I swear."
"And do you swear to preserve the peace?"
"I swear."
"Do you swear, to cast aside all selfish ambition, and to pledge yourself only to the good of the realms?"
"I swear!" Thor lifted his hammer.
"Then on this day, I, Odin Allfather, will proclaim you…" A strange look crossed Odin's face. "Frost Giants!"
It was a mad scramble to get the people to safety as the royal family made their way to the weapons vault, with the exception of Frigga. All of them knew what the Jotun would be after. They looked at bodies around the room, but nothing was stolen.
Thor said in anger, "The Jotuns must pay for what they have done!"
Odin replied, "They have paid with their lives. The Destroyer did its work, the Casket is safe, and all is well."
"All is well? They broke into the weapons vault! If the Frost Giants have stolen even one of these relics…"
"They didn't."
"Well I want to know why!"
"I have a truce with Laufey, king of the Jotuns."
"He just broke your truce! They know you are vulnerable!"
"What action would you take?"
"March into Jotunheim as you once did! Teach them a lesson! Break their spirits, so they would never dare try to cross our borders again!"
"You're thinking only as a warrior."
"This was an act of war!"
"It was the act of but a few, doomed to fail."
"Look how far they got!"
"We will find the breach in our defenses and it will be sealed."
"As king of Asgard...!"
"BUT YOU'RE NOT KING! Not yet."
The siblings left, Thor fuming. Dalla and Loki walked side by side, whispering.
"Loki, what are you planning?" Dalla asked.
"Not here and not aloud," Loki answered.
"You know I stand with you, brother."
"Since the loss of your soldier, you have become more like me. Why the change, sister?"
"After all this time, you ask it now." She shook her head. "One, you're my favorite brother. Two, nothing left to lose since most of my so-called family abandoned me after I returned broken from his death. And three, I want Thor and Odin to watch as you take the throne of Asgard, a true king."
"Do you no longer wish to rule?"
"Without my soldier, I have no reason to continue. I wish to return to Midgard, to be where he was last until my final breath."
"When I am king, I will grant you that wish."
"Then, tell me this plan so that I may grant you kingdom… King Loki."