This post covers everything relevant to Priscilla as far as the localization is concerned. It is based on a series of reddit posts from June 2018. Quotes include the official English script, my translation, and the official Japanese script in that order.
Abomination in White
A strange doll in strange dress.
There once was an abomination who had no place in this world. She clutched this doll tightly, and eventually was drawn into a cold and lonely painted world.
Funny looking doll, a funny shape not seen much.
According to a certain legend, only an undesirable held onto this. It is said that she had no place to belong anywhere in the world and was eventually guided to the cold world of a painting.
This is a peculiar doll apparently tied to a legend of a detested being. While I have filled them in for the sake of simplicity, there is no expressed pronoun used in this description. These same terms come up in Dark Souls III with the corvians’ “mythologies” to the “forlorn” hoping to also be guided to a painting, but this one is the first.
Robe worn by the alabaster-clothed guardians of the paintings in Anor Londo. Offer substantial protection versus magic.
They have guarded the Great Painting of Ariamis for ages, passing their duty down through generations, but the reason for doing so passed from all memory long ago.
Robe of the painting protectors of Anor Londo. Dimly white, smooth garment. Strong to magic.
They have protected the Great Painting of Eremias since long ago and have inherited that mission for posterity. But the reason for the mission is already long lost.
It is known that the guardians and their families have been doing this job for a very long time, but everything surrounding it has been lost to history. We have to discover that reason for ourselves, and we find our answer in Priscilla.
Soul of Priscilla the Crossbreed, trapped inside the painted world of Ariamis.
Special beings have special souls. Use the soul of this crossbreed bastard child and antithesis to all life to acquire a huge amount of souls, or to create a unique weapon.
Soul of the pure white half-dragon Priscilla, who was imprisoned in the Eremias Painting World.
Special beings possess special souls. Use the soul of the half-dragon who is an illegitimate child and enemy of life to acquire a vast amount of souls or create a unique weapon.
She was led there to be imprisoned within the world, which seems to be tied to her lineage as a literal “child of infidelity” and unique power…
Scythe born from the soul of Priscilla, the stark white crossbreed trapped inside the Painted World of Ariamis.
Even the Gods feared Priscilla’s lifehunt ability, and in the hands of a mortal, its power will turn upon its wielder.
Sickle born form the soul of the pure-white half-dragon Priscilla who was imprisoned in the Eremias Painting World.
It possesses the power of lifehunt feared by even the gods, but if the person utilizing that power isn’t the half-dragon, that power will rebound on the user.
This power is harmful even to us, not necessarily because we are “mortal” but because we are not a or the half-dragon it originates from. This is why it is safer directly using her body as the medium:
This sword, one of the rare dragon weapons, came from the tail of Priscilla, the Dragon Crossbreed in the painted world of Ariamis.
Possessing the power of lifehunt, it dances about when wielded, in a fashion reminiscent of the white-robed painting guardians.
Weapon born from the tail of the half-dragon Priscilla, the taboo sealed in the Eremias Painting World. One of the rare dragon weapons.
It possesses the power of lifehunt, and the dance-like sword technique has something in common with the painting protectors in white.
We are again reminded that she has been locked away as a forbidden something, and that there is a connection between her and the also white-colored guardians.
Curved sword of Anor Londo painting guards. Unique shape with flat tip.
The guardians, who strike down those who dare threaten the painting, attack in a continuous, circular dancing motion, a technique passed down through generations.
Curved sword of the painting protectors of Anor Londo. Has a flat-pointed, unique shape.
The consecutive attacks unleashed from the dance-like circular movements were handed down to them for generations and tore those who threaten the Great Painting to pieces.
They’ve been passing down this fighting style along with their mission for just as long. Priscilla has apparently had an important role in the painting’s history from its inception.
Key to the annex in the Painted World of Ariamis.
In the wintery painted world, there is a structure resembling an old cathedral; its annex serves as a type of storehouse.
Key for the outbuilding of the Eremias Painting World.
The snowy world of the painting is made in the shape of an old temple, and the outbuilding seems to be a kind of storehouse.
Jiin typically refers to Buddhist temples but has been applied to churches like Westminster Abbey. Nothing to indicate it is necessarily imitating a particular church, it was just intentionally painted as a snow-covered place of worship. This annex is also an outbuilding, hence why it is functioning as a storehouse of some sort.
Priscilla elaborates on the world itself:
Why could thou not let us be? Didst thou not see why Ariamis created this world?
Why don’t you leave me alone… This Eremias world is for that, isn’t it?
She was led to a prison world expressly made so that she would be left alone, implying that she has historically not been left alone…
I expected as much from thee. Why dost thee hurry toward thine death?
So you too are as I thought? Why do you all rush toward your death…?
This isn’t her first rodeo, and she has killed people who have come to kill her before. It puts her defensive posture, weapon at the ready, when we first enter in a new light.
Who art thou? One of us, thou art not. If thou hast misstepped into this world, plunge down from the plank, and hurry home. If thou seekest I, thine desires shall be requited not.
Who are you? You aren’t a friend of ours, correct? If you made a mistake and went astray, please jump down beyond here and return. And if you were seeking me, that cannot be permitted…
Despite her obvious fear of us, the intruder, she still thinks that this might all just be a misunderstanding and shows us the way out. But if we really did come here to kill her like they initially assumed, then she will kill us.
Thou must returneth whence thou came. This land is peaceful, its inhabitants kind, but thou dost not belong. I beg of thee, plunge down from the plank, and hurry home.
You, please return to your world. This place is peaceful and everyone is kind, but it is not your world, correct? Please, jump down beyond here and return.
While she has been treated well by this painting world and its inhabitants, in stark contrast to the implicitly violent and cruel world she knows outside, she is not willing to share assuming we did just accidentally slip into the painting. We have a place to belong, unlike her and the others we encountered leading up to her. They are just minding their own business, so who are we to intrude?