Her lore video was the best I've seen in a good while, and her voice acting is pretty solid. The cover was great too.
Edit: A lot of anons were freaking out over her voice and alluding to being surprised she didn't go to Hololive. Is this Beryl? I never watched her, so I wouldn't know.
Edit 2: Now that the stream is over, I've had a chance to check out Beryl's channel, and I don't think Raki sounds like her. Mannerisms seem different too. So, I have no idea who she could be. That was just my first guess, since I've seen a lot of speculation about her recently.