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Undertale AU Wiki
Undertale AU Wiki

CONTENT WARNING[]

this book isn't for the faint of heart. it contains pretty messed up things.

Introduction

Once upon a time, there were 2 races. The HUMANS, and MONSTERS. One day, a special human was born, which caused all women to go insane with lust. The male humans blamed the monsters for this, causing a great war between the 2 races. The humans eventually stood victorious and sealed the monsters underground.

Mt. Ebott, 201X

Spring

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Thank you, reader. Without you, all this wouldn’t be possible.


Disclaimer: There are things that can trigger some, so this might not be for you.

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Chapter 1: The Ruins

“Where am I? The last thing I remember is climbing Mt. Ebott, then falling down.” Frisk gets up from the bed of golden flowers. She slowly walked to the next room. A voice suddenly said “Howdy! I’m Asriel Dreemurr, one of the caretakers of the ruins.” Frisk replies, a little startled “H-hi, I’m Frisk Reap, and I fell down here. Are you what is called… A monster? Asriel said “Yes, I am. I don’t plan on hurting you, so you can trust me. However, there could be a moment when I am gone, so I think you need to know the basics first.” After a small pause, Asriel asked Frisk if she was ready. “See that heart-shaped object? That is your SOUL, the very culmination of your being. When your HP reaches 0, you’ll faint and likely die. We’ll start with white bullets. Don’t touch these, or you’ll lose HP. Next are blue bullets. Don’t move, and it will be harmless. It’s the same but reversed with orange bullets…” Some time passed. Frisk broke the silence by saying “Thank you for teaching me the basics of encounters!” Asriel said “You’re welcome. Come, I’ll lead you to my house.”! *you’ve been encountered by Froggit! Before Frisk could do anything, Asriel gave Froggit a scary glance. *Froggit felt threatened, and ran away! “Sorry, monsters can be confused and may attack while you are walking. Shall we continue?” Asriel gave Frisk a warm smile. The smile… reminds me of someone… Someone very important to me. Suddenly, Frisk collapsed. Asriel, who was caught off guard said “Are you okay?” in a rush as he quickly ran to Frisk as she passed out. Frisk woke up on a comfortable bed. There were thoughts surrounding her like “What is this place?” and “How did I get here?”. Asriel opened the door, and asked, “Are you hurt anywhere?” Frisk replied “I’m fine, other than my head feels like it’s splitting apart”. Asriel said “Here, I made chocolate pie. Enjoy it.” A door was opened and then slammed shut. “Hey Asriel, I’m home!” Asriel replied, “Hey Chara, how was training?” He said “Oh it was interesting. I got closer to winning against Asgore before he pulled a move that made me lose. I love Dad, but I’m pleasantly surprised he hasn’t kicked the bucket yet.” Asriel doesn’t look like he liked that last part. After a pause, he said “Chara, would you like some pie? I made it with you in mind” He said “Oh, yeah, I could have some right now. Training does make me hungry after all. Though I do have a question, I wonder why you were in Mom’s room? Are you still thinking about her?” Asriel replied, “No, it’s just that I found a human that fell down here, just like you did when we were kids.” He said “A-a human? Another one? It’s been such a long time, I don’t think I can even remember when the 7th human fell.” Frisk heard walking, and then she saw a human, with a green shirt that has a yellow heart locket like Asriel’s and brown shorts with black leggings. Frisk’s headache was worse. She moved the blankets off of her because she felt hot. The whole room was hot. Especially her body. It was burning. Asriel said “I know that we need a doctor, but I haven’t seen any. So, I, Asriel shall help out. Let me know if you need anything, ok? I’m not sure what you’re going through but I hope I can help.” Frisk slowly got up and hugged Asriel. “You are so friendly, Asriel. You take me in despite not knowing me and even take care of me even though I am a human. And for that, thank you. Thank you for everything.” Asriel was blushing at the comment. “Y-your welcome, Frisk. Your hug is a bit tight, could you let me go? I’ve got food to cook for all of us.” Frisk said “I don’t want to let go. I could hug you forever… My body is so hot that it’s almost unbearable Asriel. Hugging you calms it down.” Asriel shifted uncomfortably. “Really Frisk, I got to go. Chara’s waiting for me to make the food. I’ll ask him to spend some time with you. Maybe you’ll both know each other better.” Asriel yelled “Hey Chara! Can you go spend time with Frisk? She wants company while I’m cooking.” Chara came into the room and Asriel left. Frisk and Chara are both sitting on the bed and talked about things. “Sorry for making this weird, but my body feels like it’s out of control. It’s so hot… I feel like I’m losing… control… of my own body…” She got on top of Chara. “Fr-Frisk? Are you ok?” She replied “I’ll be ok soon… Hopefully” She started lifting his shirt to his surprise. He seems confused about what to do, and he looks sort of embarrassed. “Hey Frisk, can you please stop? I don’t want to do something like that with someone I just met.” Frisk kept going, despite his discomfort. He tried to get up, but he couldn’t move. “Frisk, what do you think you are-” She said “Shh, it won’t be long before I can make you feel... good.”  The last word was said soothingly, and he seemed to calm down a little. “Please Frisk, don’t do this… I’m begging you. If you don’t stop I’m afraid I’ll have to use self-defense. What if we just cuddled? That’ll be better for both of us because nobody gets harmed.” She reluctantly got off of him. “Ok, I’m sorry Chara. I lost myself for a moment.” A scary voice came from her mouth. “Your no fun.” She laid down with him and they cuddled until it was time for dinner. “Dinner is ready!” Asriel yelled. They left the room and sat down around the table. There was a strange silence in the room. Asriel broke the silence by saying "So, how are you feeling, Frisk?" She said "I'm feeling pretty much the same, though it started weakening. I think it was thanks to Chara." Chara shifted uncomfortably in his seat. "Y-yeah, don't worry about it." They finished eating. Asriel said "Hey Frisk, can you go ahead and go to bed? Since you are sick, a lot of rest would help." Frisk said "I don't think I am sick. It's not like anything I've experienced before. I don't think that a headache and high body temperature is a part of being sick, at least not like this." Asriel said, "Ok, well if you need anything I'll be on the chairiel." Frisk said “Ok, though I’m scared… what if what I am feeling is caused by the same parasite my family knows too well? If it is, then everyone is in danger. I think it would be safer to make sure Chara’s safe first. This… This parasite takes over people’s minds. It makes women go insane with lust. I, sadly know what that is like. My mom, she…she got controlled, and she…” The last part was said with Frisk trembling at remembering it. “I miss Dad… I wish he would have just listened to her and let her do it… or else he would be alive…” Frisk started crying. Asriel kind of panicked, not sure what to do to comfort Frisk. He closed his old book about 42 facts about snails and hugged Frisk. “Frisk… If you have things you want out of your system you can tell me as much as you want. How about we all go to bed, and I can talk to you in the morning when you’re awake?” Frisk calmed down and said “Ok Asriel. We’ll talk more tomorrow.” They all went to sleep. Frisk couldn’t. She couldn’t stop thinking about Asriel. Everything was dark. She didn’t notice it, but she fell asleep. “Hello Frisk” Frisk looked around. There was a whole lot of… Nothing? “Now why don’t I introduce myself properly? You’ve seen me before remember?  I resemble the look on your mother’s face when she was filled with so much lust, thanks to yours truly. Let us make a deal. Do you accept?” There was a red smile in the darkness. It scared Frisk. To accept means you live, but with the risk of me taking control, and to refuse means death by torture. So, I would recommend agreeing to it. Frisk was faced with a dilemma. Live, and possibly hurt Chara or Asriel or die by being tortured. To her, it meant the same thing. “I would rather die than be controlled by you!” It started laughing. “Your mother said the same thing as you. I see that you are just as stupid as your mother was. Since when were YOU the one in control?” Frisk woke up. She looked at the mirror. “You’re still you Frisk. We can do it, we’ll overcome Reap” She told herself. She tapped on the mirror 6 times, and a mysterious being made of crystal appeared in the mirror. "Hello, Frisk Reap." The being looked slightly cracked and with some mysterious parasite near its stomach. "It appears that you aren't having a good time," The being said jokingly. "I'm the Crystal Being, you remember me right?" It waited for a response. "Yeah, you came to me after... after..." Frisk looked down at the wood floor. "After that." The being finished the sentence for Frisk. The being's head started looking like it had animated scribbles all over it. "Visit me in that place in Waterfall. after that, I may be able to help with your condition. You'll recognize it, trust me." The being disappeared, and the mirror cracked. "I need to find this area, but I don't know what 'Waterfall' is. Maybe Asriel knows?" Frisk walked to the living room and sat on a red chair, near a fireplace. The fire was hot, but it didn't burn Frisk for some reason. "I hope he'll be back soon..." Frisk said, trailing off as she begins to fall asleep. "Hello, Frisk. Now that I am finally in you, I can start doing things." Frisk is in a dark place again. "What do you mean 'start doing things'?" The parasite cackled. "You will understand soon enough. I can give you a hint. It is enough to cause a lot of people pain." Frisk woke up suddenly. The room was still warm. A froggit was in front of her, which caught her off-guard. "Sorry, human. I didn't mean to scare you. The last time we met, I was scared off by Asriel. Let's say hi... properly this time. I'm Froggit, what's yours?" "I- I'm Frisk." "Frisk? That's a nice name. Follow me, I have something to show you." Frisk cautiously followed the Froggit. "Wait here, I'll grab the item." Froggit hopped to an area away from her sight and came back with a strange item. "Here. This should help protect you from dangerous monsters." *Frisk obtained the OLD KNIFE! "Thank you? What is it?" Froggit looked at Frisk a little confused. "You don't know what a knife looks like?" "A... a knife? I can't use this!" Frisk looked shocked and even a little angry. "Trust me, Frisk. There are dangerous monsters out there that will stop at NOTHING to end you. Even the king of monsters... Asgore may fight you. He doesn't attack Chara because he and Asriel are both Asgore's children. It would be best to leave, while you still can. Now I think you should go back before Asriel arrives." Frisk went back to the house... or at least she hoped she would. A flower stopped her midway. "Greetings, I'm Flowey. Flowey The Flower! You look lost. I can help you go back to that old place. But first... why don't we do a little friendly sparring? It would help me get these old joints working again." *Frisk encountered Flowey! "Here are a few... 'Friendliness pellets'!" Frisk dodged them, looking nervous. "You missed them. Let's try again!" 5 more pellets appeared. Frisk dodged them. "Look Ms. Flowey, I don't want to do this." The Flower laughed. "Just hit the BULLETS- I mean 'Friendliness pellets' " Frisk dodged, and calmed herself down. The Flower laughed louder. "You know what is really going on here, don't you? You just wanted to see me suffer!" Flowey laughed as her face got... larger? "DIE!" Frisk was surrounded by pellets. The pellets suddenly were on fire. It started closing in on her when suddenly a barrier stopped the pellets. Suddenly, a ball of fire hit Flowey, causing her to go back into the ground, and run away. "Are you okay Frisk?" Asriel asked. "What a horrible monster she is. Here, let me heal you." Asriel's hand had a gentle fire that healed Frisk’s scratches. They both went back to the house. Asriel broke the silence and asked, "I wonder how that even happened?" Frisk shrugged. "Well, I was following one of those Froggits, more specifically the first one we encountered. You had the wrong idea about it, it's friendly! It wanted to give me something," Frisk pulled out her old knife. "And I was given this knife. Pretty cool, right? Then Ms. Flowey attacked me." Asriel looked intrigued. "Well, that's interesting. There's something up with some of the monsters. They're acting... 'weird'. We are unsure why. Oh! I'm sorry, I started talking about my problems." Frisk was shifting uncomfortably in her seat. What does he mean by acting 'weird'? "What do you want Frisk? I got some supplies while I was out." Frisk sighed and said "I'm not hungry right now. I'm more worried about the monsters, especially if it's what I think it is. Can I walk with you there?" Asriel looked a little surprised but agreed. They left The Ruins and went into Snowdin. It was quiet at first, but small groans were heard. A snowdrake appeared out of nowhere. "Asriel, the shopkeeper needs help! We aren't sure why, but she is sweating a lot." Frisk nervously followed behind Asriel, clinging to him a little. They arrived at the shop and found the shopkeeper on the floor, trying to cool down with fans that has a strange rectangle shape, that looks like some robot. "Sho... The Shop.. is closed, please come back tomorrow." The shopkeeper began to say. "We heard you needed help" Asriel replied. "Oh! It's you Asriel. I'm not sure why, I'm just really... hot..." She got up and sat in a chair while she talked to him. Involuntarily, she grabbed his arm and pulled him somewhat close. He was very confused about what she was doing. "I'm sorry... I don't know how to control it." She began, "It's so warm right now, but for some reason, you cool me down a little..." She started to fall to the floor, and Asriel jumped in to help her up. Frisk is panicking, because she's seen it before... she's seen the look the shopkeeper is giving Asriel, which confirmed her fears. She yelled "ASRIEL! STAY AWAY FROM HER!" Asriel looked a little panicked when Frisk screamed like that out of nowhere. He started to panic even more when the shopkeeper started to corner him. He gently moved away from her. "What's wrong Frisk? You look like you've seen a ghost." Frisk is terrified. Is this what Reap meant when it said it was going to 'start doing things'? "I'm sorry Asriel," the shopkeeper said as she sat back in the chair. "I don't know what I'm doing, or even why. You are almost king, right? That means you know what to do right?" The shopkeeper said, almost crying. "It's so... hot... and I don't... even understand the first thing about why..." Frisk calmed down, but she too, started sweating. The shopkeeper left her shop and she's getting closer to Asriel. Asriel calmed down and he simply stood there, eyes closed. A barrier protected him, and another forced Frisk to stay in one spot. Frisk was surprised. "What are you doing Asriel?" He calmly spoke "It looks like you are going through the same thing as The Shopkeeper. I'm keeping you here until I can make sure my brother is safe. After that, you need to talk. You seem aware of what is happening. Asriel left to find Chara. "You know what's happening to me?" The shopkeeper asked. "...Yeah. It's The Heat caused by the parasite called Reap. It causes intense sweating, involuntary movements, and very, very high levels of... lust." She looked shocked. "Well, at least we know what is going on. Is there a cure?" Frisk sighed and said "No. You just have to wait it out. Or you can give in, but that's only a temporary fix." Both Shopkeeper and Frisk started to attack the barrier. Frisk wanted to escape, no longer able to think clearly. It felt too hot to stay in there. "So hot..." She complained. The barrier cracked. The cracks got larger and larger until the barrier broke. "I'm finally out!" Frisk has started to lose herself to Reap. Before she knew it, she tried to get on Asriel, but the Barrier prevented anything from happening. Asriel wondered "How did Frisk manage to break the barrier I trapped her in?" Chara was shocked about the condition of a lot of the monsters, and Frisk. They managed to force Frisk to go back home with them. "Do you know what is going on with our people Frisk?" Frisk didn't answer, but she smiled while she keeps hitting the barrier. The barrier cracked. Chara doesn't look happy with the silent answer. The barrier broke, cutting Frisk's finger. Frisk is losing herself even more. A new barrier was made in almost an instant. "Please answer us Frisk, we need to figure out how to deal with this situation." Frisk said in almost a demonic voice "There isn't anything to 'figure out'. You already know the answer, don't you? It's because of me, or rather a part of me that causes this." Frisk used her finger to write '=)' on the barrier. The real Frisk is trying to get herself back. She succeeds and suppresses Reap for now. "I managed to suppress it. What information do you need?" Asriel asked, "What did you mean when you said 'a part of yourself'?" Frisk calmly said "It's thanks to Reap, or rather the very reason I fell down this place to begin with. The Reap parasite runs in my family, but more specifically the female side. It causes us to do horrible things. It's able to do several things such as a 'heat wave' just like now, and it can take control of its host's mind to do things they usually don't." Asriel then asked, "How do we get rid of it?" Frisk wished she knew. "I... don't know. If I could, I would have been able to stop..." Frisk stopped talking. "We'll figure this out." Frisk laid down on her bed. "Let me heal your wound, Frisk." Asriel put his barrier down and walked inside the one he made for Frisk. He healed her wound. Frisk gently grabbed Asriel and hugged him. Asriel was confused but hugged her back anyways. "Thank you for everything you did Asriel. All you did was show me kindness... I'm sorry that this happened" Asriel looked surprised and even a little flustered. "I don't blame it on you at all Frisk, It isn't your fault. It's the parasite's." Chara said "It's probably best to stay away. Who knows when she loses herself again? Also, I have news I'd like to share. My training is almost finished. I can feel it. Next time I go to Dad's place, I'll be able to beat him!" Everyone in the room was happier after the news, brightening the room. "Well, that's something to be happy about, congrats!" Asriel looked even happier than Chara, which Frisk found funny. "Let's try to fix this situation." Frisk started to remember where she is supposed to go. "I think I figured out how, but it has to be done alone." Chara and Asriel were confused. "I need to go somewhere, but I have to do it alone." She stood up. "Okay Frisk, but first I need to make sure you can. Meet me at the door." Frisk's barrier went down and Asriel walked down the stairs. Chara left to probably eat a bar of chocolate. Frisk followed Asriel. "I need to make sure you can go alone, so..." *Frisk encountered Asriel! Small stars appeared. They slowly homed in on Frisk and got faster and faster. Frisk dodged them. "You have great dodging skills! Now can you handle this?" Fire shot up from the ground, and almost hit Frisk. There were a few more, and the last one hit. (15/20 hp) Frisk continued dodging and gave Asriel a light punch. "Good job. You passed." Asriel smiled. Frisk walked through the door. She walked through the snowy forest path and stopped at the bridge. Somebody was following her. He walked to her. "Human. Don’t you know how to greet a new pal? Turn around and shake my hand." Frisk slowly turned around and shook his hand and she heard a fart noise. "Hehehe the old whoopie cushion in the hand trick. it's ALWAYS funny. anyways, you're a human right? that's hilarious. i'm sans. sans the skeleton."