When Gaster arrived a few hours later he didn't expected Sans AND Papyrus to still be awake and watching Tv, closing the door behind him Gaster made his presence known by letting out a small cough.
"DADDY YOUR HOME!" Papyrus jumped off the sofa and ran to his fathers side and jumping up and down grabbing his lab coat.
"Papyrus what are you still doing up?" Sans at this point had gotten off of the sofa and stood behind his younger brother.
"He wanted to wait up for ya he insited on it" Gaster saw Sans and rembered why he was nervous to get home. "hey what ya got there dad?" That was when Sans pointed at the sleeping form of Scarlet.
"This is your new sister" He then places her in front of the two whilst kneeling down. "Her name is Scarlet" at this point Scarlet was waking up she began rubbing her eyes as she looked around Sans was looking at his father questioningly.
"hey dad can I have a word with ya?" Gaster swollowed a dry lump in his throat and stood up to follow Sans into the kitchen.
"Papyrus can you watch your little sister whilst Sans and I talk in the kitchen?" Papyrus nodded eagerly.
"OF COURSE I CAN I WILL BE THE BEST SISTER WATCHER" Gaster smiled and walked into the kitchen with Sans where the latter shut the door.
"so why did you create her then?" Gaster sighed.
"to be honest with you Sans I was trying to make a weapon for the king to gather more souls" Sans glared at his father.
"so what ya just gonna let them use her as a weapon? How could she even be used as a weapon she only has 1 LV?" Gaster looked away.
"its because she has your powers but much more agressiveness that your other side has" Sans glared at his father.
"WHAT! you gave her my side and you made it MORE AGRESSIVE?!" Gaster moved back slightly Sans sighed and calmed down. "So when are ya gonna have to bring her in?" Gaster sighed.
"Tommorow morning you can come if you like" Sans sighed.
"no I can't do that I can't see my little sister used as a weapon" Gaster looked down ashamed.
"I understand I truly didn't mean to create her for this life" Sans could only sigh as he walked away. Gaster followed after him to see both Scarlet and Papyrus cuddled next to each other on the sofa fast asleep.
"I'll put them to bed, Scarlet can sleep with me tonight" Sans teletported to Papyrus's room both Gaster could argue. After tucking him in he teleported to his room with Scarlet. He grabbed a spare blanket and placed Scarlet on his bed laying down next to her he placed the blanket over her and as he turned over he whispered. "goodnight lil' sis I hope I'll see ya in the morning".