oh, i really should have noticed this before, you put the sword's description in the powers section, you're supposed to put it in the weapon's section, the powers section requires you to name her special abilities and then give a specific description of what those abilities do.
for what i can see, the sword seems to make her a berserker-like character. in that case, there should be one passive ability that states that whenever she draws the blade, she becomes more easily enraged and her moral limitations are mostly removed (for example, even if she would normally not harm a friend, once she starts fighting with her sword she will gladly beat them into submission, even if not outright kill them).
then give her one active ability she can activate at will where she temporarily lets her mind succumb to the demon's influence, in this 'mode' or whatever you want to call it, you can make her faster and stronger and not feel pain anymore, but that has to be counter-balanced by far LESS precise moves (I can't allow you to simply allow her to boost all her stats by saying it 'isn't completely primal') and inability to tell friend apart from foe.
most of what is written in the powers section currently though should, as stated, be removed and instead put down in the weapon description section.
her personality section doesn't make much sense though, the edit is, honestly, kind of a lazy one, you kept it mostly identical and just added something at the end. If she is so desperate for power that she would herself put a demon in her blade, then why would she be justify the quest for Muramasa with the goal to bring order? Clearly power is its own reward in her case. Also, she defiled a sacred weapon meant for the protection of every living being on earth to attain that power, seems kind of odd that you would say that she is 'struggling to discover the right path of action for herself'. that kind of act pretty much identifies that your character is either fully convinced of the validity of their actions and the decisions they are making, or that they honestly don't care what is 'right' or not anymore, they will do what they want.
also, you do not explain why she is so hungry for power that she would commit such an outright heinous act.
In her history, you do not explain where she suddenly learned to do something as highly complicated as sealing a demon in a sword, let alone a sword of great purity that would inherently reject and purify any evil that tried to introduce itself into the weapon. You did not, either, explain why her family moved from japan to Sweden. I am not asking for a lot on that front since i did tell people that i welcomed international characters, but i will still ask for SOME explanation on that front (like blandman, who has made it evident that his character's family line got into traveling the world and living a nomadic lifestyle).
You did not, either, address the inevitable effect that Borghild's actions would have on her relation with her family, being the head who threw away hundreds of years' work to preserve the Hįvaršr for (what they would view as) 'cheap power'.
I'm sorry if i seem a bit harsh with you but i told you that i was incredibly iffy on a demonized weapon to begin with, a half-assed attempt at a character like this will not get you anywhere, especially after I had written such an extensive post earlier, offering you several suggestions on paths you could take to make this character work.