I don't know Japanese. With Google's helpful translation algorithms, however, I have discovered that this corgi is performing shiri furi, or "butt-shaking." Some people out there, enamored with the argot of our time, might be tempted to call this twerking, but it is not.
Here's more shiri furi from another angle, courtesy of YouTube user man taketyan:
There are many variations to this butt-shaking dance. There is daggering, and there is Brazilian surra de bunda, which roughly translates as "punishment of the ass." All are similar, yet different. Twerking, clearly, is an up-and-down motion, not a side-to-side one. Perhaps our corgi is trying to emulate Big Freedia's bounce moves instead?
Compare/contrast the corgi to this pup, grooving to Eminem's "Shake That":
Now, that is a twerking dog.