Just a quick authors note, Gaster!Sans will be a legend. But obviously you find out he was real all along. Typical, huh? Well, to the basics:
Y/N: Your name
F/N: Friends Name
E/C: Eye Color
H/C: Hair Color
Any question? Ask me!
LET'S DO THIS SHIT

"F/N? F/N?! Ugh. Where could she be?" It was cold out, you were walking home from your school, but it had already gotten dark. Your friend was supposed to wait for you, but as you could tell, she wasn't coming.
Earlier that day, you had gotten a text from her saying: Hey. Pick u up at school today. If I'm not there, then meet me in the alley by ur ex's house.
Yep. She went there. Your ex's. The most ruthless man there was. He was your best friend in 6th grade, not to mention your lover, and you thought he was the sweetest. But what you hadn't known was that he was also seeing other women. Women older than you.
You simply replied: k.
And that was that. After school, you waited and waited. But she never came. "Wow. Again." It was the second time she's ditched you! You were standing in the dark alley, when you saw a flash of yellow behind you. You quickly spun around, thinking it was a murderer, but there was nothing.
Hm. Better not be F/N messing with me again. You noticed that your ex's door was open, and it appeared that he was taking out trash. Please don't see... Please don't see... Too late. He saw you leaning on the ild fence that separated his house and the alley.
"Y/N? What are you doing out so late?"
"Waiting for F/N to pick me up. She hasn't texted me back yet."
He just looked at you confused, but then smirked. "Wow. I guess she's not coming? Might as well have my fun again. You owe me a blowjob..." He took a step towards you.
You silently screamed, hoping F/N was coming... But as he took another step, someone- or something walked in between you both, stopping your ex from getting any closer.
"Pretty sure she wants you gone. Leave her alone." It said, it's voice deep and low.
Your ex wasn't taking 'no' for an answer. "Listen here, twerp. Get lost, or you'll have to deal with me!" He shouted angrily at the hooded figure. He didn't listen. He just stood there in between you both.
"Excuse me?!" Your ex ran to the man, and threw a punch. But the man quickly grabbed your ex's fist and flipped him. (AND HIS NAME IS SANS CENA! XD)
You were shocked... Mostly scared of the hooded man...
"Your safe. He's not going to hurt you..." He said slowly. You only stared.
"W-who are you?" You could barely get the words out. You were trembling like crazy, and your teeth started to chatter.
"My name? I'm called Gaster Sans, but you can call me Sans... Or whatever..." He replied.
And with a blink of an eye, he was gone.

Wow. TIBIA honest, I didn't expect that. How was it? It was a short chapter, but yeah.