You looked behind you and saw... Heimdall?
Heimdall, with the bifrost sword in his hand approached you as you threw one of Kaecilius' men to the ground.
"What in Valhalla are you doing here, Heimdall?", you asked and took a step backwards causing the other attacker to stumble over and fall on his face.
"I'm just here to look after you and make sure you're safe, your father's orders.", he said and grabbed the on the ground laying man and held him up in the air, looking him straight in the eye.
"You should leave now or haven't you heard what the princess said?", Heimdall growled at the man and let him fall back on the floor.
You glanced over to Kaecillius who was shocked to see one of his man scared and the other one dead on the ground.
"This isn't over!", Kaecillius said and made a portal with his sling ring, so he and his scared man could escape.
You turned around and walked over to the man you threw on the ground.
A puddle of blood gushed out of the back of his head.
"I guess he hit his head a bit too much.", you whispered and looked back to see Heimdall missing.
Wait, Heimdall and missing? Normally he would now be here to explain things to you.
At that moment you remembered that he had called you princess instead of Y/n, which never happened in battle only in front of your father.
You decided to pay Heimdall a visit at the bifrost and ask him why he behaved this way but before you could even make your way to the bifrost Heimdall ran towards you.
"Y/n, are you okay?", he said out of breath.
"Heimdall what is wrong? Why did you disappear right behind me?"
"I wasn't here Y/n. I was on the bridge when I saw you fighting with those men and then... Then a shadow approached you, I couldn't see who it was.", he gasped for air.
"Oh dear God, sit down Heimdall I don't want you to black out.", you said and guided him to a pair of stairs and sat down next to him.
After he catches his breath he begins to explain.
"I looked over all the people in Asgard after I made sure Thor is alright and then I saw you fighting those men. I wouldn't have stepped in but when I saw a shadow behind you, someone I couldn't see through my vision I got worried about you.
Now tell me Y/n, what did he look like? "
You took a deep breath and explained Heimdall, "He looked exactly like you Heimdall, that's why I was so confused when you approached me a minute ago. I thought you were still with me after those men left but there was no trace of you, not even on the bridge.".
Heimdall was now acting serious and grabbed you by your shoulders.
" Y/n I want you to please take extra care right now. We don't know who that person might be and even if it's Loki, we do not no what his intentions are. It would be best if you immediately leave for Kamar Taj after your birthday.", Heimdall said and got up from the stairs.
You couldn't believe what he'd just said. Leave? Immediately after your birthday, which would be in five weeks? That is a bit too fast for your liking even though five weeks on Asgard are five months on Earth, it's still way too soon.
You got up and followed Heimdall into the palace and in the throne room, where a relaxing Odin sat in his throne.
"Ah, Y/n my dear. How lovely that you are already back. I guess everything is taken care of then?", Odin smiled while you gave him an angry glare.
"My King, something is happening here on Asgard. Someone is sneaking around like a shadow and is disguising as other people. I cannot identify this person because it only appears as a shadow around others. ", Heimdall spoke up and looked down at you.
"What does that mean? I thought my gatekeeper of Asgard could see everything and everyone in the universe? What is going on?!", Odin exclaimed and looked angry, you knew that it was Loki who disguised himself as Heimdall, there was no doubt about that.
"My King I think it would be safe to send your daughter to Kamar Taj immediately after her birthday, only to keep her safe."Heimdall said and now looked at Odin, who's expression hardened with his words.
"Well we should let her decide if she wants to go immediately after her birthday, since she's going to be 18 here on Asgard.", Odin said and looked at you.
(BTW I changed the age difference between the reader and Loki, he is now 3,5 years older than the reader instead of 2)