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"Kinda hard to figure out who the monster is huh?"
– Aster, Genocide Route

Aster is a mysterious Human OC created by Leroyjenkins10. He claimed to be a human ally during the War that lead to the monster's imprisonment underground, though it's proven to be a lie. He's currently working as a waiter at Grillby's.


Aster mysteriously showed up in The Underground many years ago, although it is not recorded what exact year he arrived, it is known that he showed up shortly after the barrier was created. It is unknown how he has lived so long, as humans have almost no forms of life-sustaining magic. Aster grew up very isolated mostly, teaching himself how to survive and how to make a living without having to have any direct contact to outside sources.

Aster claims to be one of the few humans on the monsters' side back during the war, but these claims cannot be backed up or dis-proven. Although picking up a job and staying with it has shown difficult for Aster, but he has recently tried musician, TV show extra and a radio host, although none have been very successful. He has struck out with his new career in the food service industry,  now a waiter at Grillby's.



  • LV. 4
  • HP: 32  
  • Attack: 15 
  • Defense: 10


  • Check 
  • Talk 
  • Tease 
  • Flirt


  • [Check Genocide] A human comedian? No matter.
  • [Check Pacifist/Neutral] A...rather intense man full of emotion. He reminds you of Sans.  
  • [Talk] He doesn't seem interested in speaking.  
  • [Tease] Really? Is that all you've got? 
  • [Tease X2] Can you PLEASE stop, like seriously dude.  
  • [Tease X3] Okay, now I'm mad!  
  • [Flirt] Haha, listen kid, flirting doesn't work on me.  
  • [Flirt X2] It's stupid too.  
  • [Flirt X3+] Kid... That option is useless. Why is it even here for me?


  Aster possesses a soul of Spite, a TRAIT thought lost long ago. Because of this, Aster can copy other traits and its abilities, and disguise his soul as the trait he mimics.  


Aster physically appears as a teenage male that has about medium-long black-brown hair with tips of red on the edges. The closer he is to be able to use his Animus magic, the redder his hair will be starting from the bottom. Once Animus mode is available for Aster, his hair becomes completely blood-red with no trace of brown.

He wears a silver belt and 2 black t-shirts with a large inverted cross at their center. Aster also has blue eyes, dark purple jeans, and mostly white boots that almost reach his knees. While in his ANIMUS form, his eyes will become completely black, and his corneas will become bright red. When comparing his size to Frisk's, Aster appears to be a foot taller than Frisk.


Aster is a very mixed character throughout life. Sometimes he's a hero, fighting off those that wish to destroy the Underground, earning the respect of some, other times he'd rather just go back to bed.  

He is generally laid-back and calm, not doing much with the general space around him. he can't be bothered to care much about as the most important thing to him is keeping his young "neice" Katie safe. he has been known  to snap at times for harsh mistreatment a certain fish gives Katie. When bored, Aster will go pick a spot to sit & read as that's one of his favorite hobbies. He has a liking for puns and knock-knock jokes, just like Sans. 

He is introverted to strangers/new people and keeps up that shell pretty well. If you are able to  break it though, he is really just like a big kid, although he can be rather snarky and sarcastic.  Not growing up like normal humans, he has yet to learn a lot about others due to being alone for so long. There are only a small group of beings that he ever really shows his emotions to. he will randomly hug people when they look upset because someone "taught" him to. Also, something of note is on the rare occasion his rage can be awoken, He will become a mindless engine of destruction.  It is for this reason he was once known as "The Blood Prince".  


  • Magnokinesis/Ferrokinesis -- enables blade barrage 
  • Soul Mimicry -- Can use various SOUL modes on himself, making battle unpredictable.  
  • Blade Barrage -- The ability to summon swords and knives and use them as attacks. 
  • Karmic Blade -- Aster summons a Blade, then slashes at his opponent. (Red attack, Large amount of damage to HP) 



The Player

The relationship between the player and Aster is ultimately based on your decisions on how to play the game. For instance, if you were on the Neutral or Pacifist route, he acts as a steadfast, albeit lazy, friend. Aster would enjoy your presence and always gets cheerful when he sees you.

But in Genocide, he still thinks of you as a friend, somewhat. He tries his best to convince you not to kill anyone anymore. As he does this, you engage into battle. Say you spare him, he'll be relieved and glad to see you had a heart of change, which turns you into the neutral. Kill him, and he says it was a mistake of his to ever meet you. However, kill Katie beforehand, And Aster will teach you an all-new meaning to the term "Bullet-hell".    


Aster enjoys Papyrus' puzzles of course, and he does enjoy spending time with him. But these two don't click a lot of the time, especially since Aster makes puns, much to Papyrus's vexation. But Pap's presence does help Aster, as Papyrus's optimism is infectious.


Aster trusts Sans, and Sans will often babysit Katie for Aster, Aster considers him a very close friend, as Katie loves Papyrus, and Sans and Aster often talk while the two play together.


Aster and Grillby are good friends, with Aster & Katie even living with Grillby's family at one point. Thick as thieves, Aster now works as a waiter in Grillby's pub. Grillby watches out for Aster, making sure if anyone in Snowdin finds out he's human, they won't squeal to any royal guardsmen about a pair of humans living on the outskirts of town. If questioned on why he goes to such lengths for a human, Grillby says; "He saved my life during the war, he's a good employee, and he pays his tab unlike a certain skeleton I know. Why wouldn't I?"


Aster's never met her. He refuses to go near Waterfall without a really good disguise.


Aster has grown to like Toriel a lot due to her kind personality. Toriel was in fact the person to teach Aster many of his attack patterns.


Aster has never seen him before, due to Blooky's shyness. But from what Aster has heard from Toriel, he's really nice. Aster wonders if he he should see this ghost who's so like him in some ways.


Aster enjoys Alphys' company and doesn't mind her over-abundance of knowledge. The two actually seemed to have formed a movie club for anime.


Muffet simply adores Katie, & has a similar soft spot for Aster too. Aster has contributed much to Muffet's cause, & she always give him and Katie an extra donut or muffin on the house. Something she never lets Aster forget. Muffet is also thankful that Aster smuggles spiders to Hotland if they leave the RUINS, so she keeps quiet about her two favorite customers being humans.


Due to Aster's disguise, Mettaton believes him to be, like many others, just an unusual monster. He may get on Aster's nerves ,but that doesn't mean they still can't be friends. Their battles are more friendly sparring than an actual life-and-death battle.

Monster Kid

Aster sees MK as a little brother. He can get on his nerves at times, but he cares a lot about the little goofball.


During his travels, Aster heard a lot about the past from his friends and various monsters, and he never really liked Asgore. Well, Aster had never went past the Core often, specifically the reason that he is now deathly terrified of the king, having seen his skill in combat during the war. And it's no exaggeration that if he was needed there or past it, he won't go there.


Flowey has tried to attack on a few occasions but mostly torments Aster with taunts. Aster knows how dangerous Flowey truly is, and makes Katie carry a spray-bottle of Herbicide For any "Yellow Echo Flowers".

W.D. Gaster




Aster's young charge. He found the young child shortly before leaving the RUINS 5 years ago.  Now almost 7, the young child sees Aster as more of a father than an uncle as she has been told. The two are as close as everyone's favorite Skele-bros, and should anything happen to Katie, well... let's just say it would end badly.


A  blue parakeet,  He's Aster's pet. He's always making up cryptic verses or sleeping. Although when needed, Phear is deadly in a fight, even for such a small bird.


Aster likes Red, enjoying her company a lot. He finds joy in watching her childish behavior, reminding him of when he was young, and she always seems to be able to cheer him up.

(Other OC's - Just ask and suggest a connection and I would be willing to add yours to the list.)


  • Despite his font-like name, he isn't related to any skeletons.  
  • He has a knack for survival, despite refusing to run from a battle even if, some say especially if, it is a lost cause. 
  • Listen to his battle theme here