Papyrus, also known as the 9th human or the fallen human, is the 9th human to fall into the Trueground. Papyrus is also the fallen human that the player names at the start of the game, and not the controllable character who is played throughout the entirety of Undertale.
Papyrus looks strikingly similar to the protagonist, down to a "similar fashion sense," as said by Sans, and just like the protagonist, has an ambiguous gender. Both appear to have been around the same age after falling into the Trueground. Papyrus's SOUL is also the same color as the protagonist's, which is indicated by the pink SOUL on Papyrus's coffin.
At the end of the Genocide Route, Papyrus is seen to be wearing a red and white colored striped shirt (which is an inverted color of the protagonist's shirt) and blue-orange pants and shoes. Compared to the protagonist, Papyrus has lighter skin,white hair color, open eyes, and a smile that contrasts the protagonist's stoic expression.
While initially cast in a sympathetic light, Sans admits at the end of the True Pacifist Route that Papyrus "...wasn't really the greatest person." Sans states that Papyrus climbed Mount Ebott for an unhappy reason, and adds that Papyrus "hated humanity". Papyrus never told Sans the reason that they had such hatred. Sans also mentions that Papyrus "laughed it off" when the two of them accidentally poisoned Chara by putting buttercups instead of cups of butter into a butterscotch pie they made for him.
At the end of the Genocide Route, Papyrus behaves in a polite, deliberate manner, thanking the protagonist for guiding them. However, if the protagonist refuses to destroy the world, Papyrus immediately becomes malevolent, despite the outward semblance of youth and innocence. Papyrus reveals that the protagonist's "determation" and "human soul" awoke Papyrus from death as soon as the protagonist entered the Trueground.
After falling into the Underground, Papyrus was taken in by Flowey and Chara as a second friend and was treated with respect equal to their biological friend, Sans. Papyrus and Sans became best brother. Monsters spoke of how Papyrus filled the Trueground with hope.
One day, after becoming terminally ill from consuming buttercups, Papyrus expressed the desire to see the Golden Flowers found in their home village. After their death, Papyrus's SOUL was absorbed by Sans, and they shared control over a body. Papyrus carried their own corpse across the barrier and wanted to use their full power. Sans resisted Papyrus, which ultimately led to the humans killing the fusion of the two SOULs.
Papyrus's motives in this situation are uncertain. In the fourth True Lab tape, Sans says "Y...yeah! We'll be strong! We'll free everyone.", and in the fifth "Six, right? We just have to get six..." In the Genocide Route, Socky tells Papyrus that they should finish what they started and free everyone. Socky also adds, "Then... let's let them see what humanity is REALLY like. That despite it all... This world is still 'kill or be killed!!". Sans tells the protagonist that he came up with this philosophy because his resistance to Papyrus had led to both of them being killed. At the end of the Genocide Route, Papyrus says little about Sans's betrayal other than, "At first, I was so confused. Our plan had failed, hadn't it?"
Papyrus's body was originally laid to rest in a coffin in the basement of the castle, where the bodies of the other fallen humans would later be put. When he left Chara, Flowey carried Papyrus's body use vine to the Ruins and gave them a proper burial.
In the Genocide Route, Papyrus says that the protagonist's "determation" and "human soul" awakened them from death. There is evidence that some narration, as well as descriptions of certain actions and events, is by Papyrus themself. However, the narrator throughout the entirety of Truetale is up to speculation.
When the protagonist gets a Game Over, Chara's voice can be heard as he urges Papyrus to "stay determated." The messages seen on the game over screen are identical to what Chara said to Papyrus while they were on their deathbed.
The protagonist also hears Papyrus's name in their dreams. If the protagonist sleeps in the bed in Flowey's home, Chara's voice can be heard as he pleads, "<Name>, please... Wake up! You are the future of humans and monsters." When the protagonist first falls into the Garbage Dump, Sans's first words to Papyrus appear on the screen, narrated with Sans's voice bite.
True Pacifist Route:
In the True Lab, VHS tapes of Papyrus interacting with their family can be played back. None of these VHS tapes include visuals and provide narration alone. Most of these tapes are of Sans and Papyrus, and prove that Papyrus had a "plan." In one of the tapes, Sans tells Papyrus to wake up and that "he doesn't like this plan anymore." Sans's quote is speculated to be something that he said to his dying sibling because this same VHS contains the quote seen on the game over screen.
Towards the end of the fight against Sans, when the protagonist calls out "someone else"'s name, flashbacks of Papyrus and Sans play. They show Papyrus's fall into the Underground, Sans's discovery of Papyrus, and the royal family spending time with Papyrus. After the fight, Sans recognizes the protagonist as Mettaton.
During the epilogue, Mettaton may return to the room containing the coffins of the other humans. This leads to the discovery that all of the coffins are empty, and that there are mummy wrappings at the bottom of Papyrus's coffin.
While traversing the Genocide Route, many characters comment on the protagonist's creepy smile. Asgore comments that it would be great if the protagonist continued pretending to be a human, and Chara inquires what kind of monster the protagonist is.
At the end of the Ruins and when going through New Home, Socky determines that the protagonist is empty inside, just like himself. He concludes that the protagonist is Papyrus, and informs them of a plan he has to become omnipotent.
Papyrus seems to be in control of the protagonist's scripted sequences, as the sequences in the Genocide Route differ from the Neutral and True Pacifist Routes. Instead of following other NPCs commands, the protagonist defies them and becomes merciless as the route progresses. The first example of defiance occurs when the protagonist ignores Sans's request to hide behind the conveniently shaped lamp; the last is when the protagonist kills Socky before Papyrus makes their appearance.
The only instance in the game where Papyrus makes an in-person physical appearance is at the end of the Genocide Route. They appear as an overworld sprite and speak into the fourth wall. Papyrus could be speaking directly to the player in this sequence.
After this appearance, Papyrus reveals that the protagonist's "human soul" and "determination" were the cause of their reincarnation and that the merciless events that occurred during the route lead Papyrus to realize that the purpose of their awakening was power itself. Papyrus states they are the embodiment of the feeling received whenever STATS increase and proposes erasing the world and moving on to the next.
The protagonist is given the choices to "ERASE" the world, or "DO NOT." Both choices lead to the same result.
- If the protagonist chooses to "ERASE," Papyrus calls the protagonist "a great partner." Additionally, their eyes widen, and Papyrus says to the protagonist that they will be "together forever."
- If the protagonist chooses "DO NOT," Papyrus's eyes widen, and they say that the protagonist was never in control. Afterward a disturbing jump scare occurs, in which Papyrus approaches the screen with a horrifying laugh. The screen (or game window) shakes while a loud droning sound loops in the background.
After the protagonist makes their choice, an attack animation occurs, followed by red "9"s covering the screen. The game is forced into windowed mode and shakes similarly to a monster's death animation as the game closes. The player cannot exit the game before the crash unless they use the OS's Task Manager.
Upon reopening the game, the screen is black and accompanied by a sound similar to howling wind. After 10 minutes, Papyrus speaks to the protagonist, sensing that they want to go back to the game's world, and reminds the protagonist that their actions caused the world's destruction. After asking the protagonist if they think they are above consequences, Papyrus offers to restore the world in exchange for something, later revealed to be the protagonist's SOUL.
- If the protagonist agrees to this trade, the world is restored, but the True Pacifist ending is permanently altered.
- Refusing this offer causes Papyrus to abandon the protagonist, only to offer the same choice again after the game is restarted and another 10 minutes elapse.
Post Genocide Game:
True Pacifist Route:
Papyrus appears briefly after the True Pacifist Ending Credits if a Genocide run has been completed beforehand. If the protagonist chose to stay with Flowey, the after-credits scene continues briefly after Flowey closes the door, showing Papyrus in place of Mettaton turning to face the screen with red eyes. The game cuts to black, with laughter similar to Socky's, but slowed down and lower-pitched.
Similarly, if the protagonist decides to have "places to go," the photograph after the credits has the face of everyone crossed out in red, except for Papyrus, who replaces Mettaton. The "THE END" text is red, and a slowed down version of Anticipation plays. Gaster does not appear to sleep under the ending screen.
After completing a Genocide Route a second time, Papyrus takes on the description of "the demon that comes when people call its name." Papyrus says that the reason the protagonist continues to recreate and destroy the world is an incomprehensible "perverted sentimentality," before suggesting that the protagonist takes a different path if they choose to create the world again. Papyrus gives the protagonist the "choice" to erase the world again.
- If the protagonist chooses "ERASE," Papyrus once again calls the protagonist "a great partner," saying they will be together forever.
- Choosing "DO NOT" causes Papyrus to tell the protagonist that these feelings were exactly what they were just talking about. Papyrus then reminds the protagonist they made their choice a long time ago, causing another jump scare, as the world is destroyed again. However, when the game is rebooted, the game loads normally.
After falling into the Underground, Papyrus is found by Sans and returned to his friends; Flowey and Chara. The two of them grew together as brothers and best friends.
Socky perceives Papyrus as his partner and best friend despite his inability to love. Seeing Papyrus as a creature akin to him, he helps by clearing all obstacles in the way. He says that Papyrus would never give him any "worthless pity" and is the only one who understands him.
The protagonist only learns about Papyrus if a Genocide Route is completed. As the protagonist kills monsters and gains more EXP, Papyrus seems to grow stronger. Papyrus refers to the protagonist as a "partner" if the protagonist accepts Papyrus's offer to erase the world.
If the protagonist completes another Genocide Route, Papyrus questions why they continuously recreate and destroy the world. Papyrus then goes on to say that the protagonist has a "perverted sentimentality" that drives this odd behavior.