Bellasiel watched carefully as the two in front of her fought and held back her instincts to go defend or stop them from fighting all together. This fight needed to happen, maybe not for Arthal but for the other man, this was a judgement of how Arthal was as a person. She had always had to watch others when she was a priestess and she learned more in seeing how others acted or moved than actually speaking with them sometimes. It was still nerve racking, both obviously skilled though she knew that Arthal wasn't taking this fight all too seriously or at least wasn't using his full fighting abilities. She would have watched it all to the end had it not been for an aura that all but grated against her senses, causing her to turn her attention to the newcomer. The man that had been next to her spoke up before she could even try to advise them not too since there was something very very off about the person before them. 

The sickness of the aura just got darker as the person spoke, as if the man next to her was just egging it on or causing more trouble by replying. The darkening however made her notice one important thing. The aura was faint, it felt different in a way and it was almost not noticeable to the eye and had she not been an elf who was sensitive to aura's other than just her own, than she may never had noticed it. The right hand was for sure a different kind of the same aura and maybe that point was weak or meant something. She had been so lost in thought, that she barely noticed that a spell had been fired at the strange man but it didn't seem to have much effect even with the spell landing a few hits. It was quick as a flash that a Fire spell was shot in return in which she actually pushed the man next to her out of the way and jumping back herself, not wanting anyone to be hit.

She twisted on her feet as she landed, jetting forward fast, hoping to catch the person by surprise as thrusted her Keyblade up under the other Keyblade of their attacker before jerking her hand to the side. The crescent part of her blade locking with the large spikes on the strangers. Not wasting another moment, she sharply yanked her Keyblade and hoped that she had surprised the strange aura man enough that he wouldn't be prepare to have to tighten his grip to keep his Keyblade in his hands. If the man didn't have his Keyblade than at least that would be a bonus till they figured out what was wrong or tried to fix it. That was her hope anyway by don't as she had but then again it could quickly back fire on her. She just didn't want anyone hurt and was willing to take the risk.