A/N: Credit to _The_Depression_ and @KaiDochiin for the ideas for this chapter and the next.
"Saaaaans!" You yelled, knocking on his door. "Get up, you lazybones! We have to pick Frisk up from visiting Muffet!" The doorknob turned. When you saw Sans, you were shocked. He looked like he hadn't slept in years. "Mornin', Y/N." He said, stifling a yawn. "Sans, are you okay? You can stay here and-" "No need, Y/N. Let's go." He said, cutting you off. You laughed. "Not so fast. Look at what you're wearing!" You said, gesturing to his pjs. He looked like he hadn't noticed them until now. "Are you sure you don't want to stay?" You asked, concerned. He waved the question away and disappeared into his room again.
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You waited at the table, stirring your coffee/tea/hot coco. Finally, you heard footsteps. "There you are, I've been waiting fo-" You stopped. "Oh, sorry Undyne. I was expecting someone else." You said, sitting down again. "Here it comes..." You thought. "Fuhuhuhu! Lemme guess, was it your boyfriend? Ya know, Sans?" She said, jeeringly. "Undyne..." You said, adding sugar to your drink. She laughed. You walked out of the kitchen, bumping into Sans. "There you are!" He said. You took his bony hand, dragging him towards the door.
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When you arrived in town, you walked past Muffet's bakery. "Y/N, we missed it. It's right he-" "I know." You said, walking. You arrived at a store. When you opened the door, a crowd of people gathered around you. "My, my! Wherever did you get that outfit?" Many people asked. You had worn Undyne's gift on that day. "A friend." You answered, dodging through the the crowd to get to the merchandise. You led Sans through rows and rows of suits. "Y/n, why are we here?" Sans said, somewhat nervously. "You need a suit for prom, don't you?" You replied, marching down another aisle. "Why'd you tell me we were picking up Frisk?" He asked. "I knew I couldn't get you to come any other way." You answered. You stopped in one aisle, looking at a certain suit. You picked it up, along with a few more.
Walking back to the front, you asked the clerk, "Where are the dressing rooms?"
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You sat on the red velvet chairs, listening to your favorite band. "Hey, Sans? You okay?" You asked, pausing your music. He hadn't said anything, which was surprising. "W-well...." He responded, shuffling his feet. "I don't know, Y/n." He said. You sighed. "Are you dressed?" You asked. "Not that it really matters, he is a skeleton, after all." You thought. "Well, yes, but I just don't know i-" You pulled back the curtain and almost died of laughter. The suit was certainly adorable, yes, but it was extremely large on him. "H-hey! It's not that funny." He said, a blue tint dusting his skull. "Come on, we'll buy it. We can get someone to tailor it to your size." You said, trying not to fall over from laughter. He closed the curtain as you sat back down. After he changed back into his regular clothes, he handed you the suit. You walked to the checkout desk and purchased the suit. "Come on, I know the perfect tailor." You said, pulling Sans toward the tailor's shop. As you walked in, the smell of expensive perfume and... roses? washed over you. You handed the tailor the suit and they led Sans into a room to tailor the suit to fit him.
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"Y/n, darling, do come here!" The robot tailor called, motioning for you to come. You walked toward Mettaton, who pulled you into the room. Sans was on a stool in the center of the room, wearing the suit, which was tailored perfectly to fit him. "A-ah! Y/n! I-wha-um-" You stopped him, hugging him. He stepped down from the stool, blue-faced. "Ooh, my OTP is canon!" He said, squealing. You both blushed. After paying Mettaton, he left for "show business."
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As you entered the house, you placed the bag containing Sans' suit on a table. You went upstairs to your room. You walked past your mirror and screamed. A small child grinned creepily at you from in the mirror. They looked very similar to Frisk, but they had red eyes, a green and yellow sweater, and paler skin. They giggled at your reaction. "Who are you?" You asked, freaked out. They said nothing, and instead gestured for you to come. You took a cautious step closer. They continued to gesture, so you came closer and put one shaky hand on the mirror. It went right through. The child seemed to glitch when your hand went through. They had blood all over them and were holding a knife. You pulled back, scared, but the image was gone. You shook your head, thinking it must've been your imagination. You took a deep breath and stepped into the mirror. For one horrible second, you saw the image again, this time with the bodies of your friend around them. And, was that Frisk with them? You fell on your hands and knees on the other side of the mirror. "Oww..." You muttered. "Oh, do you need help?" You looked up and saw a boy. Well, a goat boy. "Yeah, that'd be gr-" His hand passed through you. You looked around. The goat boy was helping up the kid in the mirror. You tried to talk to them, but they paid no attention to you. You saw the kid, watching. There were two of them? The one off to the side motioned for you to come. You stood and watched the second kid and the goat kid walked away. You started after them, but the first kid grabbed your wrist, stopping you. The scene changed. You watched as the monster brought the human child to his parents. They took the human in, raising it as their own. You watched as the two kids played. They became best friends. Then, the human became very sick. You watched as the human died. The monster, filled with grief, absorbed the human's soul. He transformed into a beast of tremendous power. You watched as he broke the barrier and carried the body of the human to a village. You thought that you saw a flash of red in his eyes. He placed the human's body in a bed of golden flowers. The villagers became angry. They shot and stabbed him, but he didn't react. He walked back through the barrier and to his Home. He collapsed in a bed of flowers. Dust spilled from the body. You looked at the first kid. They had tears in their eyes. They were black tears. You were surprised, but what wasn't surprising about this? "вяσтнєя . . . " Said the kid. The area around you was dark now. You and the kid were alone now, standing in a patch of golden flowers underground, it seemed, for a single ray of light touched the petals of the flowers. "у/и . . . . . . " Tears spilled from their eyes, now covered by their bangs. You reached over to comfort them, but they pulled away, sobbing harder. As the black tears touched the flowers, they withered and became dust. You touched the child's shoulder. They screamed and pulled out a knife. Their eyes were glowing red with hatred. "∂σит тσυ¢н мє!" They screamed, slashing your shoulder. You gasped from the pain and fell to your knees. "уσυ ѕαω ωнαт уσυя кιи∂ ∂ι∂ тσ му вяσтнєя . . . αѕяιєℓ . . . нυмαи . . . уσυ ¢αи ѕтσρ тнєιя ѕυffєяιиg. ∂σи'т ρяєтєи∂ уσυ ∂σи'т киσω ωнαт нαρρєиѕ тσ тнєм. єνєяуωнєяє тнєу gσ, ℓαυgнє∂ αт, ρυи¢нє∂, ʝєєяє∂ αт . . . уσυ ѕαω тнєм. ∂σи'т уσυ ωαит тσ нєℓρ тнєм?" The child said. "........... Yes. I want to help my friends and other monsters. But how? And who are you anyway?" You said, wincing as you moved your arm. "ιт мαттєяѕ иσт. ωнαт ωσυℓ∂ уσυ ∂σ fσя уσυя fяιєи∂ѕ? ℓєт мє нєℓρ уσυ . . . ι ¢αи мαкє тнєιя ραιи gσ αωαу . . . " You suddenly remembered Sans saying to Frisk never to give up anything to the human in the mirror, no matter what they promised. He had said a name...... Chara. You remember seeing Chara, covered in blood, holding a knife, with the bodies of your friends around them. "I would do anything for my friends....." You said, ducking your head down so they-Chara-couldn't see your face. You heard footsteps in your direction. " ι ¢ α и н є ℓ ρ у σ υ . ι ¢ α и н є ℓ ρ т н є м ." They reached out to help you up. You jump up, a f/c haze around your body. Your eyes are glowing f/c. "Including killing you." Your vision has deteriorated. You can only see white. Then, it fades into a deep blood red. Your vision slowly fades back to normal. You look around, expecting to see Chara. There is no one there. The flowers around you are wilting. You start laughing, first quietly, and then louder, maniacally. Your eyes are entirely black, except for red irises. A black liquid pools and spills from your eyes. The wilted flowers beneath you change into a hill of dead flowers. Then, as the black tears touch them, they turn into skeletons. Human skeletons, monster skeletons, even the skelebros' lifeless skeletons were there. You grinned, seeing visions appear in front of you. You watched as your "friends" ∂ιє∂ αт уσυя нαи∂ѕ. α νιиє ωяαρρє∂ αяσυи∂ уσυя ωяιѕт. тнє νιиєѕ ωяαρρє∂ αяσυи∂ уσυя αи¢ℓєѕ αи∂ σтнєя ωяιѕт. тнєу ωяαρρє∂ αяσυи∂ уσυя иє¢к. α gσℓ∂єи fℓσωєя ¢σνєяє∂ уσυя ℓєfт єує. αѕ тнє вℓα¢к тєαяѕ тσυ¢нє∂ ιтѕ gσℓ∂єи ρєтαℓѕ, тнσяиѕ вєgαи ∂ιggιиg ιи уσυя ѕкιи fяσм тнє νιиєѕ. уσυ ¢συℓ∂и'т fєєℓ ιт. α мιяяσя αρρєαяє∂ ιи fяσит σf уσυ. уσυ ѕαω α fℓσωєя ωιтн α fα¢є . . . . . fℓσωєу. уσυ αи∂ fℓσωєу ℓαυgнє∂ αи∂ ѕтєρρє∂ тняσυgн тнє мιяяσя. тнє тєαяѕ ∂ιѕѕαρєαяє∂, αℓσиg ωιтн тнє вℓσσ∂ тнαт нα∂ ¢σνєяє∂ уσυя вσ∂у ιи тнє мιяяσя. уσυя fσχ ωσкє υρ αи∂ gяσωℓє∂ αт уσυ. уσυ кι¢кє∂ ιт αѕι∂є αи∂ ωαℓкє∂ ∂σωиѕтαιяѕ αѕ fℓσωєу яєтяєα∂є∂ ιитσ α вα¢кρα¢к тнαт ℓσσкє∂ ℓιкє α fℓσωєя. уσυ ρυℓℓє∂ уσυя нαιя ιи fяσит σf уσυя єуєѕ тσ нι∂є тнєм. "нєу, gυуѕ, ι нανє α вιg αииσυи¢ємєит тσ мαкє!" уσυ ¢αℓℓє∂, тυ¢кιиg тнє киιfє fυятнєя υρ уσυя ѕℓєєνє.
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ВИ ЧИТАЄТЕ
Overtale (SansxReader)
FanfictionMonsters are free from the underground. I do not own UNDERTALE or any of the UNDERTALE characters. Warning: Very very very long. SansXReader thing. SPOILERS.