A/N: A ton of lines from this come from Thor and Thor: The Dark World. I claim nothing to them other than stitching them together to make one epic argument.
For a few days after Asta's "banishment" (as Loki would call it), he remained in his room. Finally, a servant girl knocked on his door.
"Your highness? I've brought you dinner," she said as she slowly entered.
"Leave," he muttered as she approached.
She trembled a bit as she said, "I'm sorry, Prince Loki, I didn't hear you."
"LEAVE!" Loki bellowed just before she could put the tray of food on the table.
Her shriek and the clanging of the tray on the floor was all he heard until the bliss of silence returned. Loki magically locked the door and stared into the darkness once again.
The next day, there was another knock at the door.
"I wish to see no one!" he called.
The locks he put up were magically undone and the door creaked open just a bit.
"It wasn't a request," Frigga said, pausing to give him a moment in case he wasn't decent. At his silence, she continued to enter.
Frigga approached the bed and magically pulled a chair to sit on.
"I don't want for you to see me like this," Loki said softly.
"Who can see anything in this dark room?" Frigga replied. She conjured a light orb in her hand and threw it towards the ceiling. It broke apart into dozens of fireworks that continuously burst overhead.
She smiled. "Now, that's better. There's my handsome boy."
"I know what you're doing," he mumbled.
"I don't know what you're talking about. Now, let's talk about how you treated sweet Greta. She did nothing to deserve your anger."
Loki kept his eyes focused on one firework above him. "You are right. Please give her my apologies."
"I will, and I shall make it sound much more sincere than that. Loki, look at me."
He very slowly turned to her.
Frigga refrained from rolling her eyes at his childishness. "You cannot keep in here and ignore the world, min sønn. There is still much outside of this room." (My son)
"I would prefer to stay in here, thank you."
"That sounds very lonely."
"That is what I want."
"Loki, you aren't thinking clearly. Come walk with me in the gardens."
"No, the gardens is one of the last places I would like to be." He refused to mention their tree, but Frigga knew what he meant.
"Then come to eat with us."
"No. I cannot even look at Father's face right now."
The queen sighed. "Very well. But will you at least allow meals to be brought to you? You look like you've lost weight already."
Loki sighed. "Fine."
"And no scaring the servants."
"Very well."
Frigga nodded as she stood. "I shall leave you to your loneliness then. I do hope to see you out and about soon. Jeg elsker deg, kjære sønn." (I love you, dear son)
"Jeg elsker deg også, mamma." (I love you as well, mum)
She kissed the top of his head and left, replacing the magical locks after the door closed.
After a week, Loki finally ventured out of his room. But he was even more cruel to the palace staff than before and constantly argued with Odin. Frigga begged Loki to make peace with the situation and calm down, but even his mother's pleas reached deaf ears.
For almost a year, Loki made life miserable for himself and others. He would listen to no one's implorations, even Thor and Frigga. Finally, after being called into the throne room and after perhaps their most heated argument, Odin shouted, "I should have left you on Jotuneheim where I found you!"
Loki's face fell as his eyebrows scrunched. "Wh… what?"
"You are not of this kingdom, you ungrateful brat. After the war, I found you in a Jotun palace temple. You were a runt for a frost giant, so I brought you here. Had I only known what a disappointment you'd become, I would have left you there!"
"The palace?" Loki finally choked out.
"Laufey's son," Odin confirmed.
"Laufey's son? My birthright is the Jotun throne?"
"Your birthright was to die!"
"Why? You were knee deep in Jotun blood, why would you take me?"
"You were an innocent child."
"No. You took me for a purpose. What was it?"
Odin was silent.
"TELL ME!" Loki screamed.
"I thought we could unite our kingdoms one day. Bring about an alliance, bring about permanent peace, through you. But those plans no longer matter, do they?"
"So I am nothing more than another stolen relic, locked up until you might have use for me? You could have told me what I was from the beginning! That I am the monster that parents tell their children about at night! You know, it all makes sense now, why you've favored Thor all these years. Because no matter how much you claim to love me, you could never have a Frost Giant sitting on the throne of Asgard!"
"Had I not taken you in, you would not be here to hate me."
"Then perhaps I shouldn't be here at all!" He turned around to leave.
"And where are you going?" Odin yelled.
"It's not that I don't love our little talks. It's just… I don't love them. I'll be out of your hair by nightfall tomorrow."
And with that, he left and slammed the door behind him.
That evening, he told his mother that he was leaving. Frigga was heart-broken but understood his need to leave and make his own way. She could tell he was a little hurt with her as well that she never disclosed his true heritage, but he would never tell her that.
He embraced Thor before leaving, but didn't say why he was going. He merely turned and left.
