Boobytale is a joke AU where everyone has boobies. The only monsters that weren't affected were the skeletons, the Gaster Followers, and the Amalgamates. Gaster jumped into the Core to avoid gaining his own set of breasts. He was an...unidentified monster species in this AU.



Frisk is the main character and can change between genders to their advantage.


Chara (CHAIR- uh) (that's how you pronounce it in this AU) sits at the end of the Genocide Route, waiting for you. They rip your dirty mind right out of your body, and they take your SOUL along with it.


Flowey's leaves got replaced with big coconut boobies. He attacks with "nips chips". He looks the same as he did in Undertale but with boobs and he is always blushing as he thinks that the player is "hot" and wants to bang Frisk until their Determination is gone. This is how he killed the other seven humans (including Chara). He scattered their items elsewhere.


Toriel likes to be called "Tori" in this AU. Her boobs are bigger than anyone else's boobs in the Underground (and probably the world). She wears a purple bikini with the Delta Rune symbol on the boobs. She also wears a white cape. She is reluctant towards Frisk flirting with her at the start of the game but later gives in and lets Frisk touch their boobs.


Napstablook like to be called "Blook" in this AU. They fall for the human and let the human touch their boobs. If you try to attack them, you will miss but they will figure that you don't want them near you and they will fly away, crying, and their boobs will sway.


Sans likes to be called "Sansy" in this AU. He controls his lust when you first meet him. His eye is always glowing so that he can use his magic to make boobs and tentacles. He looks about the same, but his hoodie is open and you can see his soul. He always tries to brush off flirting as jokes until you meet him. He thinks that you're cute and pushes away the love and lust until the date, where he teleports you to a room full of "Flirt Gas" and proceeds to make out with you.


Papyrus likes to be called "Papy" in this AU. He still wears his battle body, but it's black and light purple and has white splashes of liquid dripping all over it, and it isn't melted bone. He can only control his lust for a short time. When you first meet him, he only flirts for a short time and then runs away, apologizing. He later returns with full control over his lust back and talks with the player and goes on a date with them. When he feels that he can't control his lust any longer, he fights you. At the end of the battle, he makes out with you as well.


She is the head of the Royal Guard. She wears a black bra and a short black skirt. You can see lines of red paint around her wrists (these are often mistaken as cuts) and she wears small, black hoop earrings and black lipstick and eyeshadow. She will fight you until you run to the Flirt Gas containers. This is the only way to spare her. You must knock over the Flirt Gas containers so that they break. Undyne will lose all interest in fighting you and she will instead bang you until Alphys walks in.


Alphys lives in a box outside of the Lab. She doesn't work there because the king accused her guilty of lying to the public and misleading advertising. She wears her date dress always as she doesn't have anything else to wear. She walks in to Undyne banging Frisk in the Flirt Gas room and she stops them, but almost immediately Undyne pulls her in for a threesome.


Mettaton likes the change, and is addicted to Flirt Gas, as they want it for their stage. He wears exactly the same outfit as he did in Undertale. They will fight the human in box form twice, and then they will show off their "true form" and bang the human while making out with them at the same time. Alphys eventually pulls Mettaton off of the stage. Their show gets cancelled the next day.


Muffet wears a full-body swimsuit. She is not changed from the original in personality, except for being more confused as to why everyone wants to lead her to the Flirt Gas containers, as she finds the spiders more important. She will be your best friend in this AU if you like spiders, like baking, and have a clean mind (but mostly if you have a clean mind).


Everyone calls him Titgore in this AU because he has the second biggest boobs and nobody dares disrespect Toriel. His clothes are exactly the same, but he wears a flower crown instead of a gold crown. He is pure and will try and talk to you to lower your guard during battle. You have to kill him before you can move on. Alphys will revive him later.


His clothes are the same but shorter, and he isn't wearing a shirt. He is very pure. He fights...the curse. At the end, he can't keep his powers and breaks the barrier while taking everyone's boobs and dirty minds away.


Once upon a time humans and monsters lived happily on the surface together. Then one day, Alphys and a human worked together to create a vaccine that cured cancer and AIDs. But the human was actually a big meanie that tweaked it so that it gave everyone big, beautiful, MS Paint tittles. Then, Titgore declared war on humans (who were not affected). The monsters lost because it was harder to fight with tits so the humans pushed them down a hole and built a wall to keep them out with a special material the made their boobs start flailing around madly. The monsters survived because of their boobies cushioning their fall (though their breasts hurt afterwards). Alphys was fired from he job and she went to live in a cardboard box, secretly working in the Lab after hours to reverse the curse. She got the rest of the Flirt Gas put in containers and stored in the Lab. Over time, everyone became dirty minded and perverted. They couldn't focus. Then Chara fell into the Underground. People's dirty minds were gone, and it seemed like they could reverse everything and even find a way to break the barrier. But then, Asriel wanted to "fit in" and banged Chara so much that Chara died the next day from too much lust. Asriel died from the blows of people throwing dildos and vibrators and him, and suddenly, the monsters lost all hope, ad became dirtier and sluttier than ever. Only a few people controlled their lust, and Alphys was the only one able to resist Flirt Gas (as the meanie beanie they worked with gave them some vaccine).


  • Alphys is immune to Flirt Gas
  • Titgore is the one who pushed away Tori away because she was too dirty. This was before Asriel returned to the castle in his Hyperdeath form. Tori reforms by the time that Clover (Justice) falls into the Underground and after Skylar (Patience) died.
  • This is the order that the souls fell into the Underground: Determination, Integrity, Kindness, Bravery, Perseverance, Patience, Justice, Determination.
  • Asriel only banged Chara because he wanted to "fit in" with the other monsters.
  • Mettaton sniffs Flirt Gas like cocaine.
  • The idea was inspired off of RubberDuckula's OC Skoopy saying "big, beautiful MS Paint titties". I thought "Screw my reputation. I'm making an AU where everyone has boobs." And so I did.
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