I do not own Undertale only my OC

Before the monsters were placed placed underground and sealed away the king and queen were blessed with another child she looked exactly like Asreil but instead she had sky blue eyes and on the top of her head she had a streak of sapphire blue fur. She wore a long blue dress with a pattern of flowers made of mock dimonds. On the day she was born Toriel and Asgore allowed Asreil to see his little sister when he entered the room his sister was sat on the floor wearing her dress playing with several blocks. Asreil sat next to his sister and pulled out a small locket the locket was golden with blue writing written on saying 'Sapphire' the locket was in the shape of a heart after tying it around her neck he opened the locket and inside was a flower pressed inside the locket the flower was golden with a white centre. Sapphire looked at the bright object and smiled at her brother clapping her hands amused. Asreil smiled at his younger sister and hugged her close his sister returning the gesture.

A few years later Sapphire was 6 years old she had grown to become much more smart as she aged her and Asreil had only gotten closer as siblings but she had also made friends with some other monsters. One monster was a flame monster called Grillby he was a few years older than her but he treated her as a younger sister on this day Sapphire had been begging to be allowed to go to Grillby's house.

"very well but only if you remain aware of your surrondings with this war going on you are in danger with the humans" Sapphire smiled up at her parents and ran down several streets to her friends house. As she entered the house Grillby's parents sat the two children down for dinner as they ate a knock on the door alerted them all. Grillby's father went to the door looking at his wife cautiously.

"Open the door you monsters need to leave!" The monsters inside looked at each other with scared expressions. "You've lost the war all the monsters are being forced into the underground right now!" Suddenly the door was being kicked in Grillby's mother grabbed the two childrens hands whilst his father stayed back to fight. The trio ran around a corner only for a group of humans to block them stabbing Ember, Grillby's mother, and grabbing the two children. "what do we have here? Two escapee's?" But that was when the leader saw the pattern on Sapphire's dress. "hang on guys I think we have royalty. Take the walking bonfire to the other groups and we'll take the princess away" Grillby fought against the two men when one of them hit him over the head. Sapphire had to watch as they dragged Grillby away as they carried her up the mountain when they were halfway up the mountain Sapphire began to struggle. "hey quit squrming" Sapphire managed to bite the mans arm making him let go of Sapphire dropping her. Sapphire rolled down the hill landing on sharp twigs and rocks Sapphire could feel bruises beginning to form as she rolled futher down the hill. Suddenly as she reached the bottom of the hill a large rock smashed against the back of her head and then she blacked out.

A few hours later a young boy walked through the woods swiging a stick around hitting bushes and trees. As he got to a bush he heard a soft mouning pushing the plant back he saw a young monster laying on her back pulling his stick out he pointed it towards her. Walking towards her he gently placed his hand on her arm pulling her over he saw a large puddle of blood under her head. Looking back he saw no one around sighing he lifted her up and looked at the back of her head on the back of her head was a large patch of blood and under that was a crack. Using his strength the boy lifted Sapphire up and carried her to his house where his parents looked at him in shock.

"Ike why have you brought a monster into our house?" his mother asked.

"I found her out in the woods she's injured and I didn't know what to do she is only my age and I couldn't just leave her" Ike's parents looked at each other before the father said.

"Okay let me have a look at her" Ike passed her over to the dad who carried her into the spare bedroom where he cleaned the wound and wrapped a bandage around her head. Hours passed and at midnight Sapphire woke up when she woke up Ike's mother walked in with a bowl of soup placing it next to Sapphire she sat down next to her saying.

"how are you doing?"Sapphire looked at her scared. "don't worry I won't hurt you. Now what is your name?" Sapphire gave a confused look before looking at the necklace around her neck looking at it she read.

"Sapphire" The mother smiled.

"okay now do you know where your parents are?" again Sapphire gave a confused look.

"I don't know"

"okay I think you may have gotten a slight bit of amnesia from that fall you took but don't worry we shall take care of you until we find your family"

meanwhile

After Grillby had woken up he decided he had to let Asgore and Toriel know what had happend when he finally got a meeting with them he walked into the throne room Toriel saying.

"I am really worried Asgore no one has seen Sapphire what if she is hurt or worse?" Grillby then spoke up.

"um excuse me your highness?" The two looked at him and after a story later Toriel was now crying and Asgore had a depressed look but what was worse was the fact that Asreil walked in asking.

"mum, dad where is Sapphire I can't find her anywhere" Toriel kneeled down and placed her hand on his shoulder.

"My child Sapphire has been taken by some very bad people and we don't know when she will return" Asreil seemed shocked at first but then as the news sunk in tears began to fill and then he was left crying for the possible loss of his sister.