MOO AHHH THANK YOU SO MUCH FOR THIS!!
As for Perseus, I can explain!
In the RP that I run, Underfell!Grillby (a purple Grillby who’d been nicknamed purple by those in the alpha timeline) ended up getting possessed by an ancient, evil King named Groal because his own greed had drawn the king’s spirit to him. This king was a mountain of a man, chilling and horrible. He came from a timeline rich in magic and he’d wanted to devour and to own all of it. When he’d finally been killed, the blade that brought him down absorbed his corrupt soul and turned it into a gem on its hilt.
Now, because the alpha or “canon” timeline is the singularity point that doesn’t change, (when AUs are introduced, they’re sucked in from their own timelines) Prince Chara (a chara from an AU where the monsters were humans and sorcerers and the like) ended up coming along with his blade “Dreemurr’s Wrath,” the very blade that struck down Groal. Prince Chara used his powerful magic to create an oasis in the middle of the vast Snowdin woods, a place that mimicked the surface and was particularly attractive to elementals such as Grillby, Althea (an original nature elemental from the RP) and Chillzy (an original RIME elemental from the RP.)
The three elementals became fast friends and began to help the Prince to maintain “The Grove,” which was the name of the oasis, using their own magic.
Now, Underfell Grillby (henceforth referred to as Purple), fronts aggressively as this debonnaire, charming, asshole of a rich piece of smarmy shit to hide the fact that he’d honestly not like to be alone and wouldn’t mind having a friend. He’s more greedy than anyone you could meet and enjoys his wealth, power and good lucks quite a bit. He gets beaten down a few times by Chillzy and despite being upset by losses, he develops a firm respect for Chillzy which eventually blossoms into him flirting unabashedly with him. Chillzy plays along but is more keen on teasing.
Chillzy invites Purple to the Grove and Purple is reluctant as the last time he went, he fought Prince Chara, ending up humiliated because Chara’s blade was altogether too powerful. Upon entering the Grove this time, Purple feels drawn to the unguarded blade and, upon taking it up with the intent to figth Chara, he’s possessed by Groal.
Groal, already insanely powerful, overwhelms Purple’s mind and takes control of his fire, swelling him with magic and changing his form to look more like him.
Grillby is awoken from his sleep by the terrible pulse of magic he feels coming from the outside and he senses its his own magic despite that being impossible. He is contacted by Chillzy, who’s sent him a picture of Purple, only to then get a video from Chillzy involving Purple brutally sucking the magic out of his core. Grillby, with the help of Sans (who’d been over to visit), teleport to the Grove and try to stop Purple but King Groal is able to command Grillby with ease given that he’s already controlling Purple, Grillby’s “core twin.”
Devastated, Grillby and Chillzy are left in the Grove as Groal leaves to take over the Underground.
Realizing there was only one thing they could do, both Grillby and Chillzy force all of the magic out of their bodies in a desperate attempt to fuse into a new elemental with the might to defeat Groal.
From their combined powers comes the tricore, or “Perseus” (who is named by Sans.) Perseus is a “newling,” or a newly summoned elemental and while he has basic functions such as knowing how to speak and to move about due to the vague blueprints left by Grillby and Chillzy, he is not a fighter and doesn’t know the first thing about combat.
Even so, with eyes full of wonder and a duty to “protect the underground,” he dresses himself in Chillzy’s and Grillby’s clothing and does all he can to help. He stands at about six foot two, has a body of ice, steam and cloud, hands of fire and ice, and a head of ice. Fire constantly travels under the ice of his form, giving him a glittering, beautiful appearance, almost like that of the aurora borealis.
Perseus tries very hard to help people and believes very firmly that he is already everyone’s friend since he was summoned to protect everyone.
Oh, and despite the fact that Grillby and Chillzy can never technically meet him, they exist deep within, and are extremely proud of him. Because of discussions in the ooc room, @fluffymilktea drew this
to show how Chillzy and Grillby wish Perseus all the best and believe in him.