I'm a little confused here: Ushio is holding something like a bottle opener for crown caps, but the bottle has a screwed cap. How should this work?
Bottle cap challenge is done with a roundhouse kick, but Ushio is apparently just challenging herself to using a bottle cap opener on it. So long as you can get leverage, it shouldn't be hard to just plain deform the soft plastic enough to get it off, but I'm not sure how well that bottle cap opener would be able to get a grip on the cap of a size it wasn't intended for.