Sans x Magic! Reader x Chara: Under the Surface

The Door

You would spend your days in your room studying and making mental notes for the day you leave the safety of the ruins.

Toriel would go downstairs at certain hours of the day, but she would never tell you why when you asked and strictly forbade you from going down those stairs.

There was a loud knock on the heavy doors that echoed in the empty corridor as she spoke. "Who's there?"

"Spell."

"Spell who?"

"W-H-O." The voice on the other side spelled out the word, and she snorted as she laughed into her hand.

"Bravo! That was a new one." Toriel commented as she calmed down from her laughter, wiping a tear from her eye. "Now, it's my turn. Why did the skeleton want a friend?"

"I dunno, why?"

"Because he was feeling bonely." She giggled as the voice laughed along with her from the other side.

"Heheh, that's a good one. I gotta use that sometime." Sans teased as he leaned on the other side of the door. "But I think you're the one that's feeling bonely. It must be hard accepting the new policies the empress enstated. The Underground just isn't the same anymore..."

"Oh, Sans..." Toriel suddenly sighed. "Do you remember the promise you made to me?"

There was no response as Sans felt his pinpricks disappear, leaving his sockets dark and empty.

You woke up to see your once organised mess of notes in a neat pile and a slice of butterscotch pie on the desk next to you, saving it for later.

"Now's our chance." Flowey motioned with his head to the staircase and you cautiously descended the stairs one step at a time with a small candle in your hands. "The exit to the ruins is that way."

The corridor was a deep royal purple, dark and narrow leading to a dimly lit room at the end with grande doors towering over you that had a winged symbol on it just like the design on Toriel's dress as you saw she was talking to it, and hid behind the corner holding the candle close.

"I can't make any more promises, Tori..." A familiar deep voice could be heard from the other side of the large doors. "Especially after that last human two years ago, I'm just not ready for the responsibility."

"I understand..." Toriel dejectedly looked down. "Goodnight, Sans."

"Tori, wait..."

You blew out the candle and stayed still as the kind goat monster passed, sighing in relief once her long shadow disappeared up the stairs.

"I'm sorry, Tori..." Sans' voice continued after a long pause, thinking she was still there. "Paps was told he could be given an official position in the royal guard if he brought in a human soul, and you know how much he means to me."

"Sans?" You said in a scared voice and his pinpricks softened as he placed a hand on his side of the door.

"Y/n, is that you?" Sans spoke to you, his voice full of shock and uncertainty. "You really came back..."

"Sans..." You whispered as your eyes started to water, leaning against the door and slowly sliding down into a sitting position. "I miss you."

"Heh... I miss you, too." He softly chuckled. "Are you okay? You sound... really tired."

"Y/n? I hope you're not down here." Toriel's voice could be heard from the distance as her footsteps were getting louder, and you teleported back to your room.

「Sans POV」

Sans took a shortcut into his living room and was hit with the smell of strange spaghetti coming from the kitchen and the sound of Papyrus happily humming to himself as he stirred the noodles and whatever else was in the pot.

"SANS, YOU'RE JUST IN TIME FOR DINNER!" Papyrus took off his pink apron with the words bone appetite on it and left the cooking pot in the kitchen. "USUALLY YOU GO TO GRILLBY'S AFTER WORK. WHAT MAKES TODAY SO SPECIAL?"

"Well, Paps..." Sans casually started, but his brother interrupted him.

"OH, I KNOW! YOU JUST WANTED THE GREAT PAPYRUS TO COOK YOU DINNER TODAY." Papyrus proudly declared as he hurried back into the kitchen to check on his now overcooked spaghetti. "NYEH HEH HEH!"

"Hey, uh... Paps, what if I told you a human was coming?" Sans carefully worded as he followed him into the kitchen. "I know that you really wanted to-"

"WOWIE! ANOTHER HUMAN SO SOON?" Papyrus gasped, dropping the wooden spoon to pose as his scarf flowed with his movements. "SHOW ME TO THIS HUMAN, DEAR BROTHER. FOR I, THE GREAT PAPYRUS, SHALL CAPTURE THEM AND TAKE THEM TO THE CAPITAL. I'LL BE ABLE TO JOIN THE ROYAL GUARD AND EVERYONE WILL WANT TO BE MY FRIEND! AND THEN-"

"Woah, slow down, Paps..." Sans raised his hands and motioned for him to calm down his excitement. "You wouldn't want to... hurt the human, would ya?"

"OF COURSE NOT! WHAT KIND OF A MONSTER DO YOU THINK I AM?" Papyrus stomped his foot. "I WOULDN'T HURT ANYONE."

"Thanks, Paps..." Sans sighed as his brother picked him up and hugged him close, sensing he was worried. "You're the best brother ever, you know that?"

"YES, AND THAT MAKES YOU THE SECOND BEST." Papyrus gently put him down again and genuinely spoke. "I DON'T KNOW WHY YOU'RE THANKING ME, BUT YOU'RE VERY WELCOME, BROTHER."

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Y/n does not have determination so if they die, they really die like the other six kids. Chara could only be seen by Frisk and Flowey because Frisk has determination and Flowey absorbed their soul long ago so he also has some determination.